Summary

Hormones and Rep Ranges

Electromyography (EMG) Activity and Rep Ranges

Muscle Cross-Sectional Area (CSA) and Rep Ranges

Max Strength and Reps

Repetition Ranges and Their Effect on Endurance

Functional Outcomes in Elderly Individuals

Repetition Ranges and an Upper Limit

Acute Variables: Repetition Range

NASM

ACSM

AFAA

CanFitPro

PTAGlobal

ISSA

REPSI

PACE

WITS

AUSactive

CIMSPA

AUSPHYSIO

TPTA

NYPT

AOTA

<p>This course discusses the <a id="optimal" data-tip="1571" target="_blank" href="/glossary-term/optimal" class="glossary">optimal</a> repetition (reps) ranges per set of resistance training for various training goals. That is, this course details the <a id="evidence-based-practice" data-tip="1538" target="_blank" href="/glossary-term/evidence-based-practice" class="glossary">evidence-based</a> ideal reps/set for endurance, hypertrophy, strength, <a id="power" data-tip="1399" target="_blank" href="/glossary-term/power" class="glossary">power</a>, athletic performance, and functional training. The details discussed include the effect rep ranges have on <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> adaptations, the influence of rep range on short-term and long-term <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">hormone</a> concentrations, the effect on post-exercise protein synthesis, the influence of rep ranges on <a id="hypertophy" data-tip="1233" target="_blank" href="/glossary-term/hypertophy" class="glossary">muscle growth</a> and <a id="muscle-cell" data-tip="1377" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle fiber</a> type proportions, the effect on EMG activity, rep ranges for strength training with adolescents, and ideal rep ranges for improving the rate of force development for athletes.&#xA0;</p>
<p><br>Some findings from the included systematic review resulted in counter-intuitive, or at least less conventional recommendations. For example, studies suggest that low, moderate, and high rep range, when sets are performed to failure, resulting in similar increases in <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> cross-sectional area (CSA), <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> mass, and overall lean body mass. However, moderate rep ranges may result in slightly more hypertrophy, when compared to very low or very high rep ranges, due to the dependence of hypertrophy on both load and volume. And, although higher rep ranges may result in larger increases in type I fiber CSA, and lower rep ranges may result in larger increases in type II CSA, these differences likely decrease when multiple exercises are performed for each <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> group, when training volume increases, and/or an individual is more experienced with resistance training (perhaps due to high exercise volume and multiple exercises per <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> group). In summary, the research suggests that the difference between rep ranges is likely less consequential than previously thought.&#xA0;</p>
<p><br>Movement professionals (personal trainers, fitness instructors, physical therapists, athletic trainers, massage therapists, chiropractors, occupational therapists, etc.) should consider acute variables essential knowledge for <a id="optimal" data-tip="1571" target="_blank" href="/glossary-term/optimal" class="glossary">optimal</a> exercise programming, and rep range/set one of those acute variables. This course is part of our continued effort to optimize &#x201C;acute variable&#x201D; recommendations.</p>
<h3>Additional Courses:</h3>
<ul>
  <li><a href="https://brookbushinstitute.com/courses/acute-variables-repetition-tempo">Acute Variables: Repetition Tempo</a></li>
  <li><a href="https://brookbushinstitute.com/courses/acute-variables-rest-between-sets">Acute Variables: Rest Between Sets</a></li>
  <li><a href="https://brookbushinstitute.com/courses/acute-variables-circuit-training">Acute Variables: Circuit Training</a></li>
</ul>
<h3>Definitions:&#xA0;</h3>
<ul>
  <li><strong>Low:</strong> 1 - 6</li>
  <li><strong>Moderate:</strong> 6 - 12</li>
  <li><strong>High:</strong> 12 - 20</li>
  <li><strong>Very High:</strong> 20+</li>
</ul>
<p>Note: These reps ranges are generalized guidelines. It is not uncommon for research to use ranges that are in-between, or span two of these general ranges; for example, 1- 10 reps, 4 - 8 reps, or 10 -20 reps.</p>
<h3>Rep Range by Goal:</h3>
<ul>
  <li><strong>Hypertrophy:</strong> Moderate reps</li>
  <li><strong>Max Strength:</strong> Low reps (experienced), Moderate reps (novice)</li>
  <li><strong>Endurance:</strong> High Reps (adults), Moderate reps (adolescents)</li>
  <li><strong>Power:</strong> Low to moderate reps</li>
  <li><strong>Functional Outcomes in the Elderly:</strong> Moderate Reps</li>
</ul>
<p><img title="A trainer demonstrating the horizontal pull up exercise with a client" src="https://www.datocms-assets.com/25800/1649357760-horizontal-pull-up.png" alt="The horizontal pull up exercise"></p>

Course Description: Rep Range per Set

<h3>Repetition (Reps) Ranges per Set&#xA0;</h3>
<ul>
  <li><strong>Low:</strong> 1 - 6</li>
  <li><strong>Moderate:</strong> 6 - 12</li>
  <li><strong>High:</strong> 12 - 20</li>
  <li><strong>Very High:</strong> 20+</li>
</ul>
<p>Note: These reps ranges are generalized guidelines. It is not uncommon for research to use ranges that are in-between, or span two of these general ranges; for example, 1- 10 reps, 4 - 8 reps, or 10 -20 reps.</p>
<h3>Repetition Range by Goal:</h3>
<ul>
  <li><strong>Hypertrophy:</strong> Moderate reps</li>
  <li><strong>Max Strength:</strong> Low reps (experienced), Moderate reps (novice)</li>
  <li><strong>Endurance:</strong> High Reps (adults), Moderate reps (adolescents)</li>
  <li><strong>Power:</strong> Low to moderate reps</li>
  <li><strong>Functional Outcomes in the Elderly:</strong> Moderate Reps</li>
</ul>
<h3>Hormone Levels, Anabolic Signaling, and Protein Synthesis and Reps:</h3>
<ul>
  <li><strong>Testosterone and Growth <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">Hormone</a> (GH):</strong> Testosterone and GH levels following resistance training are likely to increase similarly following moderate reps and high reps, and less following low reps (when multi-joint exercises are selected and rest periods are less than 3 minutes).
    <ul>
      <li>It may be necessary to perform high rep ranges to achieve an increase in <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">Hormone</a> levels when single-joint exercises are selected, or when inter-set rest intervals are longer than 3 minutes.</li>
      <li>Resistance exercise (or inter-set rest interval) with any rep range may not significantly influence the post-exercise testosterone level of females.</li>
    </ul>
  </li>
  <li><strong>Insulin-like growth factor - 1 (IGF - 1), </strong><strong>Anabolic Signaling and Protein Synthesis:</strong> Increases in IGF-1, anabolic signaling, and protein synthesis are likely less influenced by repetition range, and more influenced by shorter inter-set rest intervals (less than 3 minutes), larger loads (intensity/effort), training to failure, potentially more total volume (reps x sets x load) of exercise.</li>
</ul>
<h3>Electromyographic (EMG) Activity and Reps:</h3>
<ul>
  <li><strong>EMG Activity: </strong>EMG activity increases as load increases. When sets are performed to failure, larger loads are generally associated with lower reps.</li>
</ul>
<h3>Increase in Cross-sectional Area (CSA) and Reps:</h3>
<ul>
  <li><strong>CSA and Reps</strong><strong>: </strong>Studies suggest that low, moderate, and high rep ranges result in similar increases in CSA when sets are performed to failure. However, there is some research to suggest that moderate rep ranges may result in slightly larger increases than low, high, or very high rep ranges.</li>
  <li><strong>CSA by <a id="muscle-cell" data-tip="1377" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle Fiber</a> Type and Reps:</strong> Higher rep ranges may result in larger increases in type I fiber CSA, and lower rep ranges may result in larger increases in type II CSA; however, it is likely that these differences decrease when multiple exercises are performed for each <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle</a> group, when training volume increases, and/or an individual is more experienced with resistance training (perhaps contributing to increases in volume, including multiple exercises per <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle</a> group).</li>
</ul>
<h3>Max Strength and Reps:</h3>
<ul>
  <li><strong>Isometric Strength: </strong>Low, and moderate rep ranges result in similar increases in isometric strength, higher rep ranges are less effective, and very high rep ranges are unlikely to result in any significant change.</li>
  <li><strong>Dynamic Strength: </strong>The dynamic strength of all groups improved less following high reps sets when compared to moderate or low rep ranges. The dynamic strength of novice lifters and women may improve similarly following low reps or moderate reps. Experienced lifters may benefit more from lower reps (higher loads) than moderate reps.</li>
</ul>
<h3>Strength Endurance:</h3>
<ul>
  <li><strong>Strength Endurance and Reps:</strong> Studies unanimously demonstrate that high reps improve strength endurance more than moderate reps; however, studies also suggest that increasing reps per set by 5 or less will not have a significant impact on results.</li>
  <li><strong>Strength Endurance for Aerobic Performance:</strong> Rep range likely has little effect on the benefits attained from strength training for improving aerobic performance.</li>
</ul>
<h3>Power Training Rep Range</h3>
<p>From <a href="https://brookbushinstitute.com/courses/strength-training/exercise-physiology/introduction-power-training-high-velocity-training/" target="_blank" rel="noopener">Power (High-velocity Training): Introduction</a></p>
<ul>
  <li><strong>Rep Range:</strong> There is currently no research comparing rep ranges for high-velocity activities, but based on the most commonly used rep ranges in <a id="power" data-tip="1399" target="_blank" href="/glossary-term/power" class="glossary">power</a> training studies, 3-10 reps/set is likely a reasonable recommendation. A more <a id="specificity" data-tip="1224" target="_blank" href="/glossary-term/specificity" class="glossary">specific</a> recommendation would be to limit repetitions to the number of reps that can be performed at maximum velocity.</li>
</ul>
<h3>Adolescents</h3>
<ul>
  <li><strong>Strength and Reps:</strong> Studies suggest that 1-RM strength in adolescents improves similarly following moderate reps or low reps; further, strength endurance also improves similarly following these rep ranges. Considering that higher loads (lower reps) may be correlated with an increased risk of injury, and higher reps may be associated with lower compliance, it may be reasonable to recommend that adolescents begin training with moderate loads and moderate rep ranges.</li>
</ul>
<h3>Functional Outcomes in the Elderly</h3>
<ul>
  <li><strong>Functional Outcomes and Reps:</strong> Elderly individuals are likely to see larger improvements in functional outcomes from moderate reps when compared to high reps, especially during longer intervention periods (more than 12 weeks).</li>
</ul>
<h3>Upper Limit of Rep Ranges:</h3>
<ul>
  <li><strong>Upper Limit:</strong> Studies imply that very high rep ranges (more than 20+ reps, less than 60% of 1-RM to failure) result in little, if any improvement in <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">hormone</a> levels, CSA, max strength or endurance.</li>
</ul>

<p>Studies have demonstrated that repetition range may influence <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">hormone</a> levels; however, additional factors are inter-related including inter-set rest period, compound vs. single-joint exercise, and volume.</p>
<h4><strong>Testosterone</strong></h4>
<p>Testosterone likely increases more following moderate or high repetition ranges (reps) when compared to low reps; however, inter-set rest interval and reps may need to be considered together. Hakkinen et al. demonstrated that testosterone increased following 10-repetition maximum (10-RM) sets, but did not increase following 1-RM sets with inter-set rest intervals of 3 minutes (1). Kraemer et al. demonstrated that 10-RM sets resulted in greater increases in testosterone than 5-RM sets with inter-set rest intervals of 1-3 minutes; however, the 5-RM group did exhibit higher levels when tested again 60-minutes post-exercise (2). Morton et al. demonstrated that high reps (20-25 reps or 30-50% 1-RM) and moderate reps (8-12 reps or 75-90% 1-RM) resulted in similar increases in testosterone with inter-set rest intervals of 1 minute (3). Conversely, Popov et al. and Vinogradova et al. demonstrated that high reps (50-60% of 1-RM) had no effect on testosterone when inter-set rest intervals were 10 minutes (4, 5). These studies suggest that testosterone levels following resistance training are likely to increase similarly following moderate reps and high reps, and less following low reps (when rest periods are less than 3 minutes). Further research is needed to investigate the effect of longer rest intervals, and the effect of intensity and rep range on changes in testosterone 60 minutes or more post-exercise.</p>
<p>Note, the majority of these studies did not include female participants (1, 3, 4, 5); however, the study by Kraemer et al. demonstrated that testosterone increased in men but not women (2). This may imply that repetition range (or inter-set rest interval) does not influence the testosterone levels of resistance training in females.</p>
<h4><strong>Growth Hormone</strong></h4>
<p>Rep range also has a significant impact on growth <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">hormone</a> (GH) levels; however, the effect of rep ranges may be influenced by the selection of compound versus single-joint exercises, and/or inter-set rest interval length. Hakkinen et al. demonstrated that moderate reps (10-reps) with compound exercises resulted in a larger increase in GH than low reps (1-rep) (1). Two studies by Kraemer et al. also demonstrated larger increases in GH following moderate reps (10-reps) with compound exercises when compared to low reps (5-reps) (2, 6). Morton et al. demonstrated that high reps (20-25 reps) and moderate reps (8-12 reps) with compound exercises resulted in similar increases in GH levels (3). However, Fink et al. demonstrated high reps (20-reps) resulted in larger increases in GH than moderate reps (8-reps) when single-joint exercises were selected (i.e. - bicep curls and tricep extensions) (9). Further, Vinogradova et al. demonstrated that high reps (50-70% 1-RM) resulted in a larger increase in GH levels than moderate reps (80-85% 1-RM) when using extended rest intervals (10-minutes between sets) (5). Last, a study by Vanhelder et al. suggests that there is a limit to how much rep range may be increased to elicit larger increases in GH, demonstrating that very high reps (28% of a 7-RM) with compound exercises had no effect on GH levels (8). In summary, moderate (10 reps) and high reps (20 reps) resulted in similar increases in GH levels when compound exercises were selected, which were higher than levels exhibited during low reps. Additionally, it may be necessary to perform high reps (20 reps) to achieve an increase in GH levels when inter-set rest intervals are long, or single-joint exercises have been selected.</p>
<h4><strong>IGF-1</strong></h4>
<p>Rep range likely has little if any influence on increases in IGF-1; however, levels of IGF-1 may be influenced by inter-set rest intervals. Studies by Kraemer et al. demonstrated that low reps (5-RM) and moderate reps (10-RM), with inter-set rest intervals of 1-3 minutes, resulted in similar increases in IGF-1 (2, 6, 7). Lamon et al. demonstrated that low reps (3-5 reps) and high reps (20-28 reps), with inter-set rest periods of 1-3 minutes, also resulted in similar increases in IGF-1 (10). Morton et al. demonstrated that moderate reps (8-12 reps) and high reps (20-25 reps) with inter-set rest periods of 1-minute resulted in similar increases in IGF-1 levels (3). Interestingly, Vinogradova et al. demonstrated that high reps (50-70% 1-RM) increased IGF-1 levels, and moderate reps (80-85% 1-RM) had no effect on IGF-1 levels; however, this study used inter-set rest intervals of 10 minutes (4). A study by Popov et al. also demonstrated that moderate reps (80% 1-RM) with inter-set rest intervals of 10-minutes had no effect on IGF-1 (3). In summary, research suggests that rep range does not influence IGF-1 levels; however, shorter inter-set rest periods (1-3 minutes) may result in a larger increase in IGF-1 than longer inter-set rest intervals (10-minutes).</p>
<h4><strong>Anabolic Signaling</strong></h4>
<p>Like IGF-1, reps may not have a significant influence on anabolic signaling (e.g. increase in mTor) and protein synthesis, as all rep ranges result in similar increases. Burd et al. demonstrated that anabolic signaling was greater than baseline following high reps (24 +/- 1.1) or low reps (5 +/- 0.2), with high reps resulting in a greater increase than low reps (11). However, Kumar et al. demonstrated that if participants did not exercise to failure, then low reps (3-9 reps) resulted in a larger increase in anabolic signaling than high reps (14-27 reps) (12). Leger et al. demonstrated that high reps (20-28 reps) and low reps (3-5 reps) resulted in similar increases in anabolic signaling when averaged over an 8-week training period (13). Last, Mitchell et al. compared the legs of each participant, demonstrating that moderate reps (80% 1-RM) and high reps (30% 1-RM), performed to failure, resulted in similar increases in anabolic signaling and hypertrophy (14). This likely implies that rep range has less influence on anabolic signaling and that other factors such as inter-set rest interval or training to failure.</p>
<h4><strong>Protein Synthesis</strong></h4>
<p>Studies have demonstrated that increases in protein synthesis mirror increases in anabolic signaling (11, 12, 14, 15). Two studies by Burd et al. demonstrated that protein synthesis increased more following high reps (24 +/- 1.1 reps); however, low reps (5 +/- 0.2 reps) also increased protein synthesis above baseline (11, 15). Kumar et al. demonstrated that when the volume was matched for each rep range, lower reps (3-9 reps) resulted in larger increases in protein synthesis when compared to higher reps (14-27 reps) (12). As mentioned above, Mitchell et al. demonstrated that moderate reps (80% 1-RM) and high reps (30% 1-RM) performed to failure, resulted in similar increases in protein signaling (14). In summary, protein synthesis is likely affected less by rep range, and more by factors such as volume, intensity, and training to failure.</p>
<table>
  <tbody>
    <tr>
      <td><strong>Summary:</strong>
        <ul>
          <li><strong>Testosterone and Growth <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">Hormone</a> (GH):</strong> Testosterone and GH levels following resistance training are likely to increase similarly following moderate reps and high reps, and less following low reps (when multi-joint exercises are selected and rest periods are less than 3 minutes).
            <ul>
              <li>It may be necessary to perform high rep ranges to achieve an increase in <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">Hormone</a> levels when single-joint exercises are selected, or when inter-set rest intervals are longer than 3 minutes.</li>
              <li>Resistance exercise (or inter-set rest interval) with any rep range may not significantly influence the post-exercise testosterone level of females.</li>
            </ul>
          </li>
          <li><strong>Insulin-like growth factor - 1 (IGF - 1), </strong><strong>Anabolic Signaling and Protein Synthesis:</strong> Increases in IGF-1, anabolic signaling, and protein synthesis are likely less influenced by repetition range, and more influenced by shorter inter-set rest intervals (less than 3 minutes), larger loads (intensity/effort), training to failure, potentially more total volume (reps x sets x load) of exercise.</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>

<p>Research demonstrates that electromyographic (EMG) activity increases with load, which is generally correlated with lower rep ranges (reps). Studies by Akima et al. and Jenkins et al. demonstrated that moderate reps (70-80% 1-RM) resulted in greater quadriceps EMG activity than high reps (30-50% 1-RM) during knee extensions (16, 17). Similarly, Cook et al. demonstrated that moderate reps (70% of peak dynamic <a id="torque" data-tip="1294" target="_blank" href="/glossary-term/torque" class="glossary">torque</a>) resulted in greater quadriceps EMG activity than high reps (20% of peak dynamic <a id="torque" data-tip="1294" target="_blank" href="/glossary-term/torque" class="glossary">torque</a>) during knee extensions (18). Studies investigating leg press and squats <a id="base-of-support" data-tip="1197" target="_blank" href="/glossary-term/base-of-support" class="glossary">support</a> the same notion of higher loads and lower reps resulting in higher EMG activity. Schoenfeld et al. demonstrated that moderate reps (75% 1-RM) resulted in greater quadriceps and <a href="https://brookbushinstitute.com/courses/biceps-femoris" target="_blank" rel="noopener">hamstring</a> EMG activity than high reps (30% 1-RM) during leg press (19). And, Looney et al. demonstrated that low reps (90% 1-RM) resulted in greater quadriceps EMG activity than moderate reps (70% 1-RM), and moderate reps resulted in greater quadriceps EMG activity than high reps (50% 1-RM) during squats (20). The same relationship is demonstrated during upper body exercises, such as the bench press and bicep curls. Studies by Sakamoto et al. and Schoenfeld et al. demonstrated that moderate reps (8-12 reps) resulted in greater <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, and triceps brachii EMG activity compared to high reps (22-30 reps) during the bench press (21, 22). And, Jenkins et al. noted the same trend with biceps curls, demonstrating that moderate reps (6-8 reps) resulted in greater biceps brachii EMG activity when compared to high (22-45 reps) reps (23). Interestingly, Sundstrup et al. demonstrated that high reps (15-reps) during a <a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">lateral</a> raise resulted in greater <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, upper <a href="https://brookbushinstitute.com/courses/trapezius-muscle" target="_blank" rel="noopener">trapezius</a>, <a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">infraspinatus</a>, and splenius capitis <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> activity compared to low reps (3-reps); however, participants only trained to fatigue in the high rep group (24). In summary, research has demonstrated that EMG activity increases with larger loads, which is generally associated with lower reps when sets are performed to failure.</p>
<table>
  <tbody>
    <tr>
      <td><strong>Summary:</strong>
        <ul>
          <li><strong>Electromyographic (EMG) Activity:</strong> EMG activity increases as load increases. When sets are performed to failure, larger loads are generally associated with lower reps.</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>
<p><img title="Dr. Brent Brookbush demonstrating a lateral lunge" src="https://www.datocms-assets.com/25800/1649424090-lateral-lunge-with-front-rack-squat.jpg" alt="A lateral lunge in a front rack position"></p>
<hr>

<h3>Upper Body Musculature</h3>
<p>Research has demonstrated that both novice and experienced, young men and women, exhibit similar increases in upper body cross-sectional area (CSA) in response to all rep ranges when sets are performed to failure. Fink et al. compared moderate reps (8 - 12 reps, 80 % 1-RM), high reps (30-40 reps, 30 % 1-RM), and mixed groups (moderate and high reps), performing isolated preacher curls for 8 weeks, demonstrating all groups exhibited similar increases in <a href="https://brookbushinstitute.com/courses/arm-muscles" target="_blank" rel="noopener">upper arm</a> CSA (25). Ogasawara et al. compared moderate reps (75% of 1-RM) and high reps (30% of 1-RM) of bench press, also demonstrating similar increases in <a href="https://brookbushinstitute.com/courses/arm-muscles" target="_blank" rel="noopener">upper arm</a> CSA (26). Schoenfeld et al. demonstrated that moderate reps (8-12 reps) and high reps (25-35 reps) of 7 exercises for major <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> groups resulted in similar increases in <a href="https://brookbushinstitute.com/courses/arm-muscles" target="_blank" rel="noopener">upper arm</a>&#xA0;CSA (27). Further, the study by Ogasawara et al. demonstrated that moderate reps (10-reps) and high reps (30% 1-RM) resulted in similar increases in <a href="https://brookbushinstitute.com/courses/pectoralis-major-latissimus-dorsi-and-teres-major" target="_blank" rel="noopener">pectoralis major</a> CSA (26). These studies suggest that moderate reps and high reps result in similar increases in CSA for upper body musculature. Chestnut et al. demonstrated that moderate reps (8-12 reps) and low reps (2-4 reps) of forearm extensor and flexor exercises to failure resulted in similar increases in CSA (28). In another study by Schoenfeld et al. using a 7 exercise full-body routine, 3 sets of 10-RM with 90-second inter-set rest intervals were compared to 7 sets of 3-RM with 3-minute inter-set rest intervals, resulting in similar increases in <a href="https://brookbushinstitute.com/courses/arm-muscles" target="_blank" rel="noopener">upper arm</a> CSA (28, 29). Last, Kraemer et al. also demonstrated that a multi-exercise full-body routine with moderate reps (8-12 reps) or low reps (3-8 reps) resulted in similar increases in <a href="https://brookbushinstitute.com/courses/arm-muscles" target="_blank" rel="noopener">upper arm</a> CSA (30). These studies comparing both low reps to moderate reps, and moderate reps to high reps, suggest that reps do not significantly influence increases in upper body <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> CSA.</p>
<h3>Lower Body: Men</h3>
<p>Similar trends are noted for lower body musculature; research has demonstrated that both novice and experienced male exercisers exhibit similar increases in lower body cross-sectional area (CSA) in response to all rep ranges, with only small differences noted in a few studies. Previously mentioned studies have compared leg extensions to failure with moderate reps (6-15 reps/80-90% 1-RM) and high reps (15+ reps/50-60% 1-RM), resulting in similar increases in thigh CSA (3, 4, 5, 14). Additional studies including Jenkins et al. comparing moderate reps (80% 1-RM) and high reps (30% 1-RM) of leg extensions, and Tanimoto et al. comparing relatively slow reps (50% 1-RM) and normal speed reps at (80% 1-RM) of leg extensions, also demonstrated similar increases in thigh CSA (31, 32). A previously mentioned study by Schoenfeld et al. included several lower body exercises, but also demonstrated that moderate reps (8-12 reps) and high reps (25-35 reps) resulted in similar changes in thigh CSA (27). Further, previously mentioned studies by Lamon et al. and Leger et al. demonstrated that low reps (3-5 reps) and high reps (20-28 reps) resulted in similar increases in quadriceps CSA (10, 13). In summary, these studies demonstrate that low, moderate, and high rep ranges result in similar increases in lower body <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> CSA, in male exercisers.</p>
<p>A few studies suggest that some small differences may exist between rep ranges. Weiss et al. compared 3-5 RM, 13-15 RM, and 23-25 RM squat training groups, demonstrating similar changes in <a href="https://brookbushinstitute.com/courses/biceps-femoris" target="_blank" rel="noopener">hamstring</a> thickness; however, the moderate and high reps groups did exhibit more thigh CSA than the low reps group (33). Further, the two previously mentioned studies by Popov et al. and Vinogradova et al. demonstrated that moderate reps (80-85% 1-RM) resulted in a greater increase in <a href="https://brookbushinstitute.com/courses/gluteus-maximus" target="_blank" rel="noopener">gluteus maximus</a> CSA when compared to high reps (50% 1-RM) (4, 5). These studies may suggest that increases in CSA are correlated with total volume, intensity, or certain muscles may be more <a id="prone" data-tip="1561" target="_blank" href="/glossary-term/prone" class="glossary">prone</a> to hypertrophy than others. Two additional studies compared rep ranges when sets were not performed to failure. Tanimoto et al. demonstrated that 3 sets of high reps (50% 1RM) of leg extensions, with sets not performed to failure, resulted in no increase in quadriceps CSA (34). Conversely, Holm et al. compared a high volume (10-sets) program with sets not performed to failure, to high reps (36-reps) program with sets performed to failure, demonstrating similar increases in quadriceps CSA (35). These studies may imply that sets to failure are not necessary to achieve increases in CSA; however, the alternative may be very high volume as used in the Holm et al. study (34). Further, research is recommended to determine ideal rep versus volume ratios. Two studies have compared rep ranges in elderly individuals (60+ years old). Kalapotharakos et al. demonstrated that moderate reps (8-reps) of leg extensions performed to failure resulting in a greater increase in thigh CSA than high reps (15-reps) (36). And, Van Roie et al. compared high reps (10-15 reps) to very high reps (80-100 reps) of leg extensions, demonstrating similar increases in thigh CSA in elderly men (37). These studies suggest that elderly men may benefit more from moderate reps than high or very high rep ranges. In summary, there is some research suggesting that moderate rep ranges may result in larger increases than low, high, or very high rep ranges for certain lower body muscles, in young and elderly men.</p>
<h3><strong>Lower Body: Women</strong></h3>
<p>Research has also investigated the influence of rep range on thigh (quadriceps and <a href="https://brookbushinstitute.com/courses/biceps-femoris" target="_blank" rel="noopener">hamstrings</a>) cross-sectional area (CSA) in women; however, the available studies have only included participants with little or no resistance training experience. In a study mentioned above, Kraemer et al. compared a multi-exercise full-body routine with moderate reps (8-12 reps) to the same routine with low reps (3-8 reps), demonstrating similar increases in thigh CSA (30). Hisaeda et al. compared 4-5 sets of 15-20 RM to 8-9 sets of 4-6 RM of leg extensions, also demonstrating similar increases in thigh CSA (38). Schuenke et al. compared a routine of leg press, squats, and knee extensions with standard speed and moderate reps (6-10 reps), slow speed of moderate reps, and a standard speed of high reps (20-30 reps), demonstrating that only the high reps group exhibited no improvement in quadriceps CSA (39). This study, like others, may imply an upper limit for rep ranges. Two studies compared rep ranges when sets were not performed to failure. Bemben et al. compared a total body routine with moderate reps (8-reps) or high reps (16-reps), not performed to failure, in postmenopausal women (mean age of 51.4 +/- 5.5), demonstrating both routines resulted in similar increases in rectus femoris CSA (40). And, Taaffe et al. demonstrated that elderly women (60+ years old) performing leg press, knee extension, and knee flexion exercises for 3 sets with moderate reps (7-reps) exhibited a larger increase in thigh CSA than 3 sets of high reps (14-reps) (41). Interestingly, both of these studies included relatively high volume programs, which may be congruent with similar studies on men which demonstrated that increases in CSA may be achieved when sets are not performed to failure if volume is sufficient and perhaps relatively high. Last, two studies mentioned above also included elderly women, Kalapotharakos et al. demonstrated that moderate reps (8-reps) of leg extensions performed to failure resulting in a greater increase in thigh CSA when compared to high reps (15-reps) (36). And, Van Roie et al. compared high reps (10-15 reps) to very high reps (80-100 reps) of leg extensions to failure and demonstrated similar increases in thigh CSA (37). In summary, research on women suggests similar responses to resistance training as studies on men. There is some research suggesting that moderate rep ranges may result in larger increases in CSA than low, high, or very high rep ranges; however, the differences are likely small.</p>
<p><img src="https://www.datocms-assets.com/25800/1645403842-human-anatomy-cross-sectional-diagram-leg-muscles-tendon-bone-en_medical512.jpeg" title="Cross sectional view of the lower leg muscles, including gastrocnemius, soleus, and tibialis muscles" alt="Cross sectional view of the muscles of the lower leg"></p>
<h3>Repetition Ranges and Their Effect on Muscle Fiber Type Cross-Sectional Area</h3>
<p>The effect of rep ranges on the cross-sectional area (CSA) of individual fiber types (type I or II) has been investigated in several studies. Vinogradova et al. demonstrated that moderate reps (80-85% 1-RM) resulted in greater increases in type II fiber CSA, and high reps (50% 1-RM) resulted in greater increases in type I fiber CSA when performing multiple sets of a single exercise (leg press) (5). Netreba et al. also demonstrated that moderate reps (85-90% 1-RM) resulted in a greater increase in type II fiber CSA, and high reps (20-25% 1-RM) resulted in a greater increase in type I fiber CSA when performing multiple sets of a single exercise (leg extension) (42). These studies imply that the resulting increases in CSA from certain rep ranges are <a id="specificity" data-tip="1224" target="_blank" href="/glossary-term/specificity" class="glossary">specific</a> to fiber type; however, additional studies suggest less <a id="specificity" data-tip="1223" target="_blank" href="/glossary-term/specificity" class="glossary">specificity</a>. Mitchell et al. demonstrated that performing leg extension with moderate reps (80% 1-RM) or high reps (30% 1-RM) resulted in similar increases in type I and II fiber CSA in the vastus lateralis of experienced male exercisers. (14). Campos et al. demonstrated that high reps (20-28 reps) and low reps (3-5 reps) resulted in similar increases in type I and type II fiber type CSA when performing multiple exercises (leg press, squat, and knee extension) with novice exercisers (43). Similarly, Morton et al. demonstrated that individuals with at least 2-years of resistance training experience exhibited similar increases in type I and type II fiber CSA following 12 weeks of whole-body resistance training with moderate reps (8-12 reps) or high reps (20-25 reps) (3). And, counter to some of the previous studies, Dons et al. compared sets of leg extensions to failure with 50% of 1-RM and 80% of 1-RM, demonstrating that the fiber type proportion of the vastus lateralis did not change; however fast-twitch fiber area increased significantly more in the 50% 1-RM group (44). In summary, there is some evidence to suggest that higher rep ranges may result in larger increases in type I fiber CSA and lower rep ranges may result in larger increases in type II CSA; however, it is likely that these differences decrease when multiple exercises are performed for each <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> group, when training volume increases, and/or an individual is more experienced with resistance training (perhaps contributing to increases in volume, including multiple exercises per <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> group).</p>
<table>
  <tbody>
    <tr>
      <td><strong>Summary:</strong>
        <ul>
          <li><strong>CSA and Reps</strong><strong>: </strong>Studies suggest that low, moderate, and high rep ranges result in similar increases in CSA when sets are performed to failure. However, there is some research to suggest that moderate rep ranges may result in slightly larger increases than low, high, or very high rep ranges.</li>
          <li><strong>CSA by <a id="muscle-cell" data-tip="1377" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle Fiber</a> Type and Reps:</strong> Higher rep ranges may result in larger increases in type I fiber CSA, and lower rep ranges may result in larger increases in type II CSA; however, it is likely that these differences decrease when multiple exercises are performed for each <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle</a> group, when training volume increases, and/or an individual is more experienced with resistance training (perhaps contributing to increases in volume, including multiple exercises per <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle</a> group).</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>
<p></p>

<h3>Isometric Strength</h3>
<p>Research has investigated the effect of various rep ranges on isometric strength. Note, all studies were performed with young inexperienced exercisers, an exercise frequency of three times per week, and training periods ranging from 6-12 weeks. O&#x2019;Shea et al. demonstrated that low reps (2-3 reps) and moderate reps (9-10 reps) of leg extensions resulted in similar increases in knee extension maximal voluntary isometric contraction (MVIC) (45). Fisher et al. demonstrated that moderate reps (avg reps of 9.66 +/- 1.94) and high reps (avg reps of 20.16 +/- 4.6) resulted in similar increases in knee extension MVIC (46). However, Hisaeda et al. noted a difference in rep ranges, demonstrating that low reps (2-5 reps) resulted in a greater increase in knee extension MVIC than high reps (15-20) (38). These studies likely imply that lower rep ranges result in larger increases in strength, but that similar benefits can be attained from a relatively wide range of repetitions, for example, 8 - 20 reps may result in similar increases in isometric strength. Additional studies demonstrate similar findings for upper body musculature. Studies by Fink et al. demonstrated that moderate reps (8-reps) resulted in a larger increase in elbow flexion MVIC compared to high reps (20-reps) (9, 25). And, Holm et al. demonstrated that very high reps (60 reps at approximately 15.5% 1RM) did not improve knee extension MVIC (35). These studies likely imply that for increasing isometric strength low and moderate rep ranges result in similar increases, higher rep ranges are less effective, and very high rep ranges are unlikely to result in any significant increase.</p>
<h3>Single-joint Dynamic Strength</h3>
<p>Research has investigated various rep ranges and their effect on dynamic strength during single-joint exercises. Note, these studies were performed on young, inexperienced exercisers, training with a frequency of three times per week for 7-12 weeks. Hisaeda et al. demonstrated that knee extension exercises with low reps (4-5 reps) resulted in greater increases in knee extension dynamic strength compared to high reps (15-20 reps) (38). Aagard et al. demonstrated that isolated knee extension and flexion exercises with moderate reps (8-reps) resulted in greater increases in knee extension and flexion dynamic strength compared to high reps (24-reps) (47). Similarly, Holm et al. demonstrated that moderate reps (8-reps) resulted in greater increases in knee extension dynamic strength compared to high reps (36-reps) (35). These studies suggest that lower rep ranges are more beneficial for increasing strength than higher rep ranges when performing single-joint exercises. Several additional studies have investigated the effects of rep range on strength when performing multi-joint exercises (e.g. squats or leg-press). Weiss et al. demonstrated that low reps (3-5 reps), moderate reps (13-15 reps), and high reps (23-25 reps) of squats resulted in similar increases in knee extension and flexion dynamic strength (48). Further, Netreba et al. demonstrated that moderate reps (6-10 reps) and high reps (35-50 reps) of leg press resulted in similar increases in knee extension and flexion dynamic strength (42). An additional study by Netreba et al. demonstrated moderate reps (80-85% 1-RM) and high reps (50% 1-RM) of several multi-joint exercises also resulted in similar increases in knee extension and flexion dynamic strength (49). These studies suggest that lower rep ranges increase strength more than higher ranges when performing single-joint exercises; however, the difference in strength gained from various rep ranges decreases when performing multi-joint exercises or multiple exercises.</p>
<h3>Bench Press 1-RM Strength</h3>
<p>Research has investigated various rep ranges and their effect on bench press 1-repetition maximum (1-RM) strength. Note, these studies included young participants training 3-4 times per week and training periods of 8 - 24 weeks. Berger et al. demonstrated that moderate reps (4-8 reps) resulted in a greater increase in bench press 1-RM strength when compared to low reps (2-reps) in novice male exercisers (50). Further, Anderson et al. demonstrated that moderate reps (6-8 reps) resulted in a greater increase in bench press 1-RM strength when compared to high reps (30-40 reps) in novice male exercisers (51). These studies suggest that moderate reps result in larger improvements in bench press 1-RM strength compared to low reps or high reps for this group; further, studies including female exercisers demonstrate similar trends. Kraemer et al. demonstrated that low reps (3-8 reps) and moderate reps (8-12 reps) resulted in similar increases in bench press 1-RM strength in novice female exercisers (30). Further, Stone et al. demonstrated that moderate reps (6-8 reps) resulted in a greater increase in bench press 1-RM strength compared to high reps (15-20 reps) in novice female exercisers (52). These studies suggest that females may respond similarly to low and moderate rep ranges; however, similar to men high reps are not as effective for improving strength. Additional studies have included experienced male exercises. Schoenfeld et al. demonstrated that low reps (2-4 reps) resulted in a greater increase in bench press 1-RM strength compared to moderate reps (8-12 reps) in experienced male exercisers (29). Previously mentioned studies Morton et al. and Schoenfeld et al. demonstrated that moderate reps (8-12 reps) resulted in a greater increase in bench press 1-RM strength when compared to high reps (20-35 reps) in experienced male exercisers (3, 27). This suggests that low reps result in larger improvements than moderate reps, and moderate reps result in larger improvements than high reps in experienced male exercisers for bench press 1-RM strength. In summary, research suggests that novice lifters are likely to exhibit similar increases in 1-RM bench strength with low or moderate reps, and high reps are less effective. However, experienced exercises are likely to improve 1-RM bench strength more with lower rep ranges than moderate reps.</p>
<p><img src="https://www.datocms-assets.com/25800/1649713391-dumbbell-chest-press.jpg" title="Dr. Brent Brookbush demonstrating a dumbbell chest press" alt="A client performing a dumbbell chest press"></p>
<h3>Squat 1-RM Strength</h3>
<p>Research has investigated the effect of various rep ranges on squat strength as measured by a 1-repetition maximum (1-RM). Note, all studies included young participants, an exercise frequency of 2-3 times per week, and training periods of 6 - 24 weeks. Schoenfeld et al. demonstrated that low reps (2-4 reps) resulted in a greater increase in squat 1-RM strength when compared to moderate reps (8-12 reps) in men (29). Similarly, Campos et al. demonstrated that low reps (3-5 reps) resulted in a greater increase in squat 1-RM strength when compared to moderate reps (9-11 reps) in men (43). And, Weiss et al. demonstrated that low reps (3-5 reps) resulted in a greater increase in squat 1-RM strength when compared to high reps (13-15 reps) in men (4). Conversely, women may not respond differently to low and moderate reps. Kraemer et al. demonstrated that low reps (3-8 reps) and moderate reps (8-12 reps) resulted in a similar increase in squat 1-RM strength in young women (30). Note, the lack of difference may also be related to training experience, as alluded to in the studies investigating 1-RM bench press strength. Last, Rana et al. demonstrated that moderate reps (6-10 reps) resulted in a greater increase in squat 1-RM strength when compared to high reps (20-30 reps) in women (53). These studies suggest that lower rep ranges result in a greater increase in 1-RM squat strength; however, women may not experience significant differences between low and moderate rep ranges (this may also be attributable to training experience).</p>
<h3>Elderly 1-RM Strength</h3>
<p>A relatively large number of studies have compared moderate and high repetition ranges (reps) and their effect on 1-repetition maximum (1-RM) strength in the elderly. de Vos et al., using pneumatic machines, demonstrated that moderate reps (80% 1-RM) resulted in a greater increase in 1-RM strength compared to high reps (20% 1-RM) (54). Fatouros et al. demonstrated that a multi-exercise, whole-body routine with moderate reps (6-8 reps) resulted in a greater increase in 1-RM strength compared to high reps (14-16 reps) (55). Similarly, Willoughby et al. demonstrated that a whole-body routine of moderate reps (8-10 reps) resulted in a greater increase of 1-RM strength when compared to high reps (15-20 reps) (56). Studies by Kalapotharakos et al. demonstrated that moderate reps (8-10 reps) resulted in a greater increase in lower body 1-RM strength compared to high reps (15-20 reps); however, improvements in function were similar for both groups (57). Last, as mentioned above, Van Roie et al. compared high reps (10-15 reps) to very high reps (80-100 reps) of leg extensions, demonstrating that very high rep ranges did not increase 1-RM strength in elderly men (37). This research suggests that 1-RM strength improves more for elderly individuals with moderate reps when compared to high reps; however, the function may improve similarly with moderate and high reps, and very high rep ranges may not result in any benefit.</p>
<h3>Early Post-menopausal Woman and 1-RM Strength</h3>
<p>Two studies investigated the effect of rep range on 1-RM strength for early postmenopausal women. Note, the studies used machine-based exercise programs. Kerr et al. demonstrated that moderate reps (8-reps) and high reps (20-reps) resulted in similar increases in leg press, bicep curl, and tricep extension 1-RM strength following a 1-year long program (58). Similarly, Bemben et al. demonstrated that moderate reps (8-reps) and high reps (16-reps) resulted in similar increases in leg press, knee flexion, lat pulldown, seated row, bicep curl, and tricep extension 1-RM strength following a 6-month program (42). Interestingly, the study by Bemben et al. demonstrated that the moderate reps (8-reps) group exhibited larger increases for shoulder press and knee extensions (42). In summary, moderate reps and high reps are likely to result in similar increases in 1-RM strength for early postmenopausal women; however, moderate reps may result in a small additional amount of 1-RM strength. Further, research is needed.</p>
<table>
  <tbody>
    <tr>
      <td><strong>Summary:</strong>
        <ul>
          <li><strong>Isometric Strength: </strong>Low, and moderate rep ranges result in similar increases in isometric strength, higher rep ranges are less effective, and very high rep ranges are unlikely to result in any significant change.</li>
          <li><strong>Dynamic Strength: </strong>The dynamic strength of all groups improved less following high reps sets when compared to moderate or low rep ranges. The dynamic strength of novice lifters and women may improve similarly following low reps or moderate reps. Experienced lifters may benefit more from lower reps (higher loads) than moderate reps.</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>
<p><img title="A box jump exercise, used for improving lower body power" src="https://www.datocms-assets.com/25800/1649513015-box-jump-mike-1.png" alt="A client performing a box jump"></p>
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  <tbody>
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      <td>
        <h3>Power Training and Reps</h3>
        <p>From <a href="https://brookbushinstitute.com/courses/strength-training/exercise-physiology/introduction-power-training-high-velocity-training/" target="_blank" rel="noopener">Power (High-velocity Training): Introduction</a></p>
        <ul>
          <li><strong>Rep Range:</strong> There is currently no research comparing rep ranges for high velocity activities, but based on the most commonly used rep ranges in <a id="power" data-tip="1399" target="_blank" href="/glossary-term/power" class="glossary">power</a> training studies, 3-10 reps/set is likely a reasonable recommendation. A more <a id="specificity" data-tip="1224" target="_blank" href="/glossary-term/specificity" class="glossary">specific</a> recommendation would be to limit repetitions to the number of reps that can be performed at maximum velocity.</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>

<h3><strong>Young Novice Exercisers</strong></h3>
<p>Several studies suggest that higher rep ranges result in larger increases in <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> endurance in young, novice exercisers. Schoenfeld et al. demonstrated that high reps (25-35 reps) resulted in a greater increase in bench press endurance (number of reps to failure with 50% 1-RM) when compared to moderate reps (8-12 reps) (27). Anderson et al. demonstrated that very high reps (100-150 reps) and high reps (30-40 reps) resulted in a greater increase in bench press endurance (as many reps as possible with 40% 1-RM) when compared to low reps (6-8 reps) (51). Mitchell et al. demonstrated that high reps (30% 1-RM) of leg extensions resulted in a larger increase in knee extension endurance (number of reps to failure with 30% 1-RM) when compared to moderate reps (80% 1-RM) (14). And, Rana et al. demonstrated that high reps (20-30 reps) resulted in a greater increase in Smith machine squats, leg press, and knee extension endurance (as many reps as possible with 60% 1-RM) when compared to moderate reps (6-10 reps) (53). These studies unanimously demonstrate that higher rep ranges result in larger increases in <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> endurance than moderate or low rep ranges in young, novice lifters. Further research is needed to investigate the effect of higher rep ranges on the strength endurance of experienced exercisers.</p>
<h3><strong>Elderly Novice Exercisers</strong></h3>
<p>Two studies investigated the effect of rep ranges on strength endurance in the elderly, demonstrating a similar trend as noted in younger exercisers. Van Roie et al. demonstrated that high reps (80-100 reps) resulted in a larger increase in knee extension endurance (number of reps to failure with 60% 1-RM) when compared to moderate reps (10-15 reps) in <strong>elderly, novice exercisers</strong> (37). And, Vincent et al. demonstrated that high reps (13-reps) and moderate reps (8-reps) resulted in similar increases in chest press and leg press endurance (as many reps as possible with 60% 1-RM) in <strong>elderly, novice exercisers</strong> (61). Note, the study by Vincent et al. which demonstrated no significant difference compared a smaller difference between rep ranges. This may imply that larger differences in rep range are necessary to optimize improvements in strength endurance (61). Again, studies unanimously demonstrate that high reps improve strength endurance more than moderate reps; however, studies also suggest that increasing reps per set by 5 or less will not have a significant impact on results. Similar to studies on novice exercises, further research is needed to investigate the effect of higher rep ranges on the strength endurance of experienced, elderly lifters.</p>
<h3><strong>Effect on Treadmill and Bike Ergo Endurance Testing</strong></h3>
<p>Studies investigating the effect of strength endurance training on aerobic endurance activity suggest rep range may not be a significant factor. Jackson et al. demonstrated that high reps (20-reps) and low reps (4-reps) resulted in no change in VO2 peak during a cycle ergometer <a id="assessment" data-tip="1482" target="_blank" href="/glossary-term/assessment" class="glossary">test</a> in <strong>young participants experienced in the sport of cycling</strong> (62). Vincent et al. demonstrated that high reps (13-reps) and moderate reps (8-reps) resulted in similar increases in VO2 peak and time to exhaustion during a graded treadmill <a id="assessment" data-tip="1482" target="_blank" href="/glossary-term/assessment" class="glossary">test</a> in <strong>elderly, novice exercisers</strong> (63). Conversely, Netreba et al. demonstrated that high reps (20-25% 1-RM) resulted in a greater increase in VO2 Max during a cycle ergometer <a id="assessment" data-tip="1482" target="_blank" href="/glossary-term/assessment" class="glossary">test</a> when compared to moderate reps (60-70% 1-RM) or low reps (85-90% 1-RM) in <strong>young, novice exercisers</strong> (49). Studies suggest that rep range likely has little effect on the benefits attained from strength training for improving aerobic performance. Although the study by Netreba et al. suggests that high reps may be more beneficial, the load was so low (25% of 1-RM) and the rep range was so high (performed until failure), the exercise might be classified as resisted aerobic or anaerobic threshold training.</p>
<table>
  <tbody>
    <tr>
      <td><strong>Summary:</strong>
        <ul>
          <li><strong>Strength Endurance and Reps:</strong> Studies unanimously demonstrate that high reps improve strength endurance more than moderate reps; however, studies also suggest that increasing reps per set by 5 or less will not have a significant impact on results.</li>
          <li><strong>Strength Endurance for Aerobic Performance:</strong> Rep range likely has little effect on the benefits attained from strength training for improving aerobic performance.</li>
        </ul>
      </td>
    </tr>
  </tbody>
</table>
<p><img src="https://www.datocms-assets.com/25800/1649713999-cycling.jpg" title="Bikers in a group during the The Peloton of the Tour de France" alt="Image of bikers during the Tour de France"></p>
<div class="mw-mmv-image-metadata-column mw-mmv-image-metadata-desc-column">
  <div class="mw-mmv-image-desc-div">
    <p class="mw-mmv-image-desc">The Peloton of the Tour de France, 9th of July 2005 at the begin of the ascend to Cote de Bad Herrenalb. Jan Ullrich (Deutsche Telekom) at about the 10th position (before the CSC rider, Basso?). Levi Leipheimer is behind the CSC rider. https://en.wikipedia.org/wiki/Cycle_sport#/media/File:TourDeFrance_2005_07_09.jpg</p>
  </div>
</div>
<table>
  <tbody>
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      <td>
        <h3>Adolescents, Strength, and Reps:</h3>
        <p>Two studies have investigated the effect of rep range on increases in 1-RM strength and strength endurance in adolescent boys and girls. Faigenbaum et al. demonstrated that moderate (6-8 reps) and high reps (13-15 reps) elicited a similar increase in 1-RM chest press strength in adolescents (59). And, Assuncao et al. demonstrated that low reps (4-6 reps) and moderate reps (12-15 reps) elicited a similar increase in 1-RM bench press and Smith machine squat strength in adolescents (60). Additionally, Assuncao et al. demonstrated that these rep ranges resulted in similar increases in strength endurance (reps until failure at 70% of 1-RM) (60). In summary, studies suggest that 1-RM strength in adolescents improves similarly following moderate reps or low reps; further, strength endurance also improves similarly following these rep ranges. Considering that higher loads (lower reps) may be correlated with an increased risk of injury, and higher reps may be associated with lower compliance, it may be reasonable to recommend that adolescents begin training with moderate loads and moderate rep ranges.</p>
      </td>
    </tr>
  </tbody>
</table>
<p></p>

<p>Moderate and high repetitions (reps) and their effect on functional outcomes have been investigated in elderly, novice exercisers. Van Roie et al. demonstrated that moderate reps (10-15 reps) resulted in a larger improvement than very high reps (80-100 reps) on various functional tests, including 6-minute walking distance, chair sit-to-stand <a id="assessment" data-tip="1482" target="_blank" href="/glossary-term/assessment" class="glossary">test</a>, and maximal gait speed in elderly, inexperienced exercisers (37). Fatouros et al. demonstrated that moderate reps (6-8 reps) resulted in a greater increase in walking speed (the time it took to walk 25-feet, turn around, and walk another 25-feet), and the timed up and go <a id="assessment" data-tip="1482" target="_blank" href="/glossary-term/assessment" class="glossary">test</a> when compared to high reps (14-16 reps) (55). These studies suggest that moderate reps improve sit-to-stand and gait speed more than high reps or very high reps. The study by Fatouros et al. also demonstrated that moderate reps (6-8 reps) resulted in a greater improvement in stair climbing speed (the time it took to walk up and down 8-steps with a 2.3-kilogram weight) when compared to high reps (14-16 reps) after a 24-week intervention (55). Conversely, Kalapotharakos et al. demonstrated that moderate reps (8-reps) and high reps (15-reps) resulted in a similar increase in stair climbing speed (the time it took to walk up 4-steps); however, the intervention was only 12 weeks long (57). These studies likely imply that moderate reps result in larger improvement in stair climbing than high reps; however, the difference may only be noted following longer training periods. In summary, elderly individuals are likely to see larger improvements in functional outcomes from moderate reps when compared to high reps, especially during longer intervention periods (more than 12 weeks).</p>
<p><img title="Trainer working with an older client" src="https://www.datocms-assets.com/25800/1649649545-senior-fitness.jpg" alt="An older client working out with a trainer"></p>

<p><span>Several studies imply there is an upper limit to the number of repetitions per set that is beneficial. Vanhelder et al. demonstrated that very high reps (28% of a 7-RM) did not change GH levels when using compound exercises in young participants (8) (Note, other studies reviewed in this course demonstrated lower rep ranges with compound exercises have a significant effect on GH). Van Roie et al. compared high reps (10-15 reps) to very high reps (80-100 reps) of leg extensions to failure and demonstrated similar increases in thigh CSA in elderly men (37). Schuenke et al. compared low, moderate, and very high rep ranges, demonstrating that only the very high rep range group (20-30 reps) exhibited no increase in </span>quadriceps<span> CSA, in a group of novice, female exercisers (39). Holm et al. demonstrated that very high reps (60-reps or 15.5% 1-repetition maximum) did not change knee extension isometric strength (35). And, Anderson et al. demonstrated that very high reps (100-150 reps) and high reps (30-40 reps) resulted in similar increases in bench press endurance (51), suggesting that very high reps resulted in no additional benefit. These studies imply that very high rep ranges (more than 20+ reps, less than 60% of 1-RM to failure) result in little, if any improvement in <a id="hormone" data-tip="1266" target="_blank" href="/glossary-term/hormone" class="glossary">hormone</a> levels, CSA, max strength, or endurance.</span></p>

Bibliography

<p>© Brent Brookbush 2020</p>
<p>Questions, comments and criticisms welcomed and encouraged.</p>

Copyright

A-Band - Refers to the part of the muscle cell that looks darker under a microscope.  This area of the cell is darker due to parallel arrangement of thicker filaments (myosin) and overlap with the thinner filaments (actin).
<ul>
 	<li>As a muscle contracts, the A-band is where actin and myosin interact.</li>
</ul>
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

<strong>Accuracy</strong> - the proportion of individuals correctly identified by the test results.
<ul>
 	<li>For example, a special test with perfect accuracy would imply a test has 100% specificity, 100% sensitivity, 100% positive predictive value and 100% negative predictive values.</li>
</ul>

Action Potential - A rapid change in voltage, resulting in a wave of excitation, that may result in stimulation of a nerve or muscle cell.
<ul>
 	<li>In order for an action potential to be initiated, the resting membrane voltage must exceed the excitation threshold, which then results in a cascade of depolarization and the "wave of excitation." Any stimulus below that threshold will not result in an action potential, and a stimulus greater than the threshold will not increase a single action potential, but may result in additional action potentials.  In this way, the action potential functions more like an on/off switch (all or none), and less like a dimmer switch.</li>
</ul>

A single-joint movement pattern (most often) designed to load a specific under-active muscle(s), while minimizing the contribution of over-active synergists via specific cues/joint motions.
<ul>
 	<li style="text-align: left;">Activation techniques/exercises are performed with the intent of addressing a muscle exhibiting a reduction in activity (tone) as a result of, or contributing to postural dysfunction.</li>
 	<li style="text-align: left;">Activation techniques/exercises cannot be multi-joint movement patterns due to relative flexibility, altered reciprocal inhibition, and synergistic dominance resulting in compensation patterns.</li>
</ul>
Example, <a href="https://brentbrookbush.com/articles/corrective-exercise-articles/activation/gluteus-medius-activation-progression/" target="_blank">gluteus medius activation</a> involves resisted hip abduction while minimizing the contribution of the TFL via hip extension.

Active stretching is a term used to describe a stretch that involves an active contraction of opposing musculature to lengthen a muscle to its end range. Generally these stretches are held for 2-5 seconds and repeated for 8-15 repetitions.

<strong>Adenosine triphosphatase (ATPase):</strong> is the enzyme responsible for catalyzing (initiating and accelerating) the decomposition of ATP to ADP.
<ul>
 	<li>This dephosphorylation (breakdown) reaction releases energy for processes like muscular contraction.</li>
</ul>

<b>Adenosine triphosphate (ATP): </b>The molecule that functions as a universal energy-transfer molecule, providing most of the energy associated with muscular contraction and human movement. ATP is composed of an adenine group, a ribose group, and three molecules of inorganic phosphates.
<ul>
 	<li>Energy is provided when hydrolysis results in the cleaving of a phophate group; resulting in adenosine diphosphate, an inorganigic phosphate group, and energy.</li>
</ul>

<strong>Algometry</strong> - measuring the amount of pressure to result in sensitivity or pain, using an algometer.
<ul>
 	<li>Generally, research uses algometry to establish a minimum pain pressure threshold (PPT), in which a lower PPT implies more sensitivity and pain, and a higher PPT implies less sensitivity and pain. PPT is a common outcome measure in trigger point research.</li>
</ul>
<a href="https://brentbrookbush.com/wp-content/uploads/2019/07/Algometer.jpg"><img class="aligncenter  wp-image-140177" src="https://brentbrookbush.com/wp-content/uploads/2019/07/Algometer.jpg" alt="Image of an Algometer" width="500" height="333" /></a>

<span class="_Tgc"><b>All-or-none</b> <b>principle</b> - a nerve or muscle cell's response to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds the threshold potential (threshold of an action potential), the nerve or muscle fiber will respond completely; otherwise, there is no response.</span>

Example, when a motor unit in the biceps brachii is stimulated it contracts the same way whether a 10 lb or 50 lb dumbbell is lifted.  It is actually the number of muscle cells and the size of the motor unit that determines force output.

&nbsp;

The transition period between eccentric load and concentric contraction during a repetition of an exercise.  This term is most often used in reference to power/plyometric exercises, in which a shorter amortization phase is believed to be beneficial.  The shorter amortization phase may better use the stored energy from the elastic deformation of connective tissue and enhance synchronization of myotatic (stretch) reflex with maximum voluntary contraction.

Example, the athlete was cued to spend as little time as possible in the bottom of their squat stance (the amortization phase) during a set of box jumps.

Muscles that oppose the prime mover and synergists for a given joint action.

That is, all the muscles that can perform the opposing joint action.

Example: The triceps and anconeus are antagonists during elbow flexion.

An anatomical direction; toward the front

Example, the face is on the <em>anterior</em> aspect of the head

<strong>Appendicular Skeleton</strong> - referring to the bones the bones of the arms and legs, as well as the bones that support them. This includes the pelvis, clavicle and scapula. There are approximately 126 bones in the appendicular skeleton.
<ul>
 	<li>Etymology - Appendicular, as in appendage, "that which is appended to something as a proper part," 1640s, from <a class="crossreference" href="https://www.etymonline.com/word/append?ref=etymonline_crossreference">append</a> + <a class="crossreference" href="https://www.etymonline.com/word/-age?ref=etymonline_crossreference">-age</a>. - <a href="https://www.etymonline.com/word/appendage" target="_blank" rel="noopener">Etymology Online</a></li>
</ul>
"Appendicular skeleton" is a label referring to a set of bones whose function is distinct from the bones of the "<a href="https://brentbrookbush.com/glossary/axial-skeleton/" target="_blank" rel="noopener">axial skeleton</a>".

A reflexive decrease in muscle activity due to joint dyskinesis.
For example, a reduction in deep cervical flexor activity as a result of cervical spine dyskinesis.

<strong>Arthrokinematic Motion</strong> - Small amplitude motions between bone surfaces at a joint.  The arthrokinematic motions are roll, glide (slide or translation), spin, compression and distraction (traction). Arthrokinematic motions accompany osteokinematic motions to maintain joint congruence.
<ul>
 	<li>Example, arthrokinematic motion of the talus includes posterior glide on the tibia during ankle dorsiflexion.</li>
</ul>
Synonyms include: arthrokinematics, passive accessory motion, joint play and component motion

&nbsp;

<strong>Assessment</strong><em> -</em> is the act of assessing, i.e. determining the importance, size, or value of -

In most cases, the results of an assessment are compared to normative data. If the individual exhibits values that are within normal parameters, it may be assumed that the aspect of health or motion assessed is not contributing to the patient's complaint, symptoms or movement impairment. If the results fall outside of normal parameters, it may indicate that the aspect of health or motion assessed is contributing to, or being affected by the patient/client's complaint, symptoms, or movement impairment. In some cases, the results of an assessment are compared to an "ideal model." In this case, deviations from the ideal are noted as potential issues. For example, deviations noted in the <a title="Introduction to the Overhead Squat Assessment" href="https://brentbrookbush.com/online-courses/articles/assessment/introduction-overhead-squat-assessment/" target="_blank">Overhead Squat Assessment</a> are compared to an "ideal model" of posture and motion.

Assessments used by human movement professionals can be divided into three broad categories:
<ul>
 	<li><strong>"Clear" the Patient/Client for Intervention</strong> - These are tests, assessments and evaluations used to determine if a patient/client's issue may improve given the assessing professional's scope, skills, abilities and willingness to treat that individual.
<ul>
 	<li>For example, many of the special tests used in orthopedic medicine assist in determining the level of pathology or likelihood of a particular diagnosis. Certain issues and diagnoses are beyond the scope of the human movement professional, and are better treated by diagnostic professionals in the medical community (physicians, podiatrists, surgeons, etc.). A <em>Calf Squeeze (Thompson) Test</em> is one example, in which a positive sign may indicate a rupture of the Achilles tendon that may be better treated via surgical intervention.</li>
</ul>
</li>
 	<li><strong>Highlight Contraindications - </strong>Tests, assessments and evaluations used to stratify risk or preclude a professional from addressing certain tissues, motions or using a particular technique.
<ul>
 	<li>For example, the Vertebral Artery Test (VBI) is often used to determine if high velocity thrust mobilizations (manipulations) are safe for a patient with cervical dysfunction.</li>
</ul>
</li>
 	<li><strong>Refine Exercise/Intervention Selection</strong>: Tests, assessments and evaluations used to assist the professional in determining which techniques, modalities and exercises will best address a patient/client's complaints or desired goals.
<ul>
 	<li>Most movement assessments fall into this category. For example, a positive <a href="https://brentbrookbush.com/vimeo_videos/elys-test-rectus-femoris-flexibility-assessment/" target="_blank">Ely's Test</a> may indicate a need to release and/or lengthen the <a href="https://brentbrookbush.com/articles/anatomy-articles/muscular-anatomy/rectus-femoris/" target="_blank">rectus femoris</a>.</li>
</ul>
</li>
</ul>
Note: An assessment, or assessment result, may fall into more than one category. For example, although goniometry is an assessment most often used to <em>Refine Exercise/Intervention Selection</em>, if a range of motion is significantly altered, with an abnormal end-feel, and/or causes the patient or client/pain, the individual may need to be referred to a physician for further testing and <em>Clearance</em> to resume rehab activities.  Further, that same patient may return to the human movement professional with a list of <em>Contraindicated Activities</em> from the physician. - <em>"When in doubt, refer out!"</em>

<strong>Axial Skeleton</strong> - referring to the bones of the head, neck, trunk and spinal column (does not include pelvis). There are approximately 80 bones in the axial skeleton.
<ul>
 	<li>Etymology - Axial, as in "axis", referring to "imaginary motionless straight line around which a body (such as the Earth) rotates," from Latin <span class="foreign">axis</span> "axle, pivot, axis of the earth or sky" - <a href="https://www.etymonline.com/word/axis" target="_blank" rel="noopener">Etymology Online</a></li>
</ul>
"Axial skeleton" is a label referring to a set of bones whose function is distinct from the bones of the "<a href="https://brentbrookbush.com/glossary/appendicular-skeleton/" target="_blank" rel="noopener">appendicular skeleton</a>".

<strong>Balance</strong> - The ability to maintain a body’s center of mass over its base of support. Balance can be static or dynamic.
<ul>
 	<li>For example, maintaining balance is harder on one leg because the center of mass must stay over a much smaller base of support.</li>
</ul>

A ball and socket joint (also called a spheroid joint or spheroidal joint) is a synovial joint in which the rounded or spherical end of one bone fits into a cup-like depression of another bone. The distal bone is capable of motion around an indefinite number of axes, which have one common center. Examples include the hip and shoulder (glenohumeral joint)

<strong>Base of support (BoS)</strong> - refers to the area beneath an object or person, and the area within the perimeter created by every point of contact that the object or person makes with the supporting surface. This may include the <a href="https://brentbrookbush.com/articles/anatomy-articles/muscular-anatomy/gluteus-maximus/" target="_blank" rel="noopener">glutes</a> of someone sitting on a chair, or the back of someone leaning against a wall.
<ul>
 	<li>For example, during a single leg balance the BoS is the area of the foot in contact with the surface; however, when a person is standing on two feet, the BoS is the area of both feet and the surface between them.</li>
</ul>

Pertaining to both sides

Example, bilateral rows are performed with both arms at the same time.

<strong>Case-control Study</strong> - a particular form of retrospective study that samples a matched group of people who have, and do not have the outcome being studied. A case-control study is a quasi-experimental design, often used in medicine to aid in determining potential contributing factors (cannot determine causality). In this study type exposure is the dependent variable and outcome is independent.
<ul>
 	<li>Example, in this retrospective case-control, medical records were investigated for trends correlated with cervical pain (1).
<ol>
 	<li>Mäkela, M., Heliövaara, M., Sievers, K., Impivaara, O., Knekt, P., &amp; Aromaa, A. (1991). Prevalence, determinants, and consequences of chronic neck pain in Finland. <i>American journal of epidemiology</i>, <i>134</i>(11), 1356-1367.</li>
</ol>
</li>
</ul>

An anatomical direction; toward the tail, relative to humans this term is often used to refer to "in the direction of the tale (toward the feet)".

Example, to release the trapezius muscle the therapist used a force directed<em> caudally</em>.

<strong>Center of mass (CoM)</strong> - an object's mean position of mass; that is, a point that is perfectly surrounded by an equal amount mass in all directions.

<b>Center of gravity (CoG)</b> - point where <b>gravity</b> appears to act. Since the human body is so small compared to the earth, we can assume gravity acts uniformly on the body, and that CoG and CoM are the same.
<ul>
 	<li>Example, the CoM of the human body while lying down or standing straight up is close to our navel. However, it is possible that during a resistance exercise, the combination of the body's weight and the weight of the resistance will place the combined CoM outside the body. For example, during the mid-portion of a <a href="https://brentbrookbush.com/vimeo_videos/back-squat/" target="_blank" rel="noopener">back squat</a> the CoM would be several anterior to the naval.</li>
</ul>

An anatomical direction; toward the head (synonym: cranial)

Example, hip pain was felt with any force directed <em>cephalad</em>.

<strong>Cohort Study</strong> - a particular form of longitudinal study that samples a cohort (a group of people who share a defining characteristic), performing a cross-section at intervals through-out a period of time. A cohort study is a quasi-experimental design often used in medicine to aid in determining etiology or a cause-and-effect relationship. In this study type exposure is the independent variable and outcome is dependent.
<ul>
 	<li>Example, the study by Cholewicki et al. (1) investigated Yale Varsity Athletes (the cohort) with 2 and 3 year follow up (longitudinal design) and found that trunk muscle response time to off-loading was predictive of future low back injury.</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/core/increased-trunk-muscle-latency-may-cause-rather-than-result-from-low-back-pain/" target="_blank" rel="noopener noreferrer">Cholewicki, J., Silfies, S., Shah, R., Greene, H., Reeves, N. Alvi, K., Goldberg, B. (2005). Delayed trunk muscle reflex responses increase the risk of low back injuries. Spine. 30(23), 2614-2620</a></li>
</ol>

<strong>Comparable Sign:</strong> A combination of pain, stiffness and/or spasm during examination that is comparable to the patients symptoms.
<ul>
 	<li>One common error made during evaluation with special tests is attention given to any discomfort or pain, rather than attempting to identify the pain/discomfort related to the patient's complaint (concordant/comparable sign). Many special tests purposefully test tissue limits and are at least mildly uncomfortable in every individual. Basing your assessment on positive tests that resulted in "concordant/comparable signs" will improve your chances of arriving at the correct diagnosis.</li>
</ul>

An alternative movement pattern that has been adopted to compensate for dysfunction/impairment in the human movement system.
Example: A lack of calf extensibility may limit dorsiflexion, leading to the knees bowing inward (functional valgus) and excessive forward lean of the torso during a squat.

An arthrokinematic motion - the approximation of joint surfaces; that is, a force that directs one bone surface into another resulting in a reduction in intra-articular volume. Although widely thought of as a "destructive force", it is likely best to consider compression as a naturally occurring, stabilizing force. Any arthrokinematic force in excess (spin, glide, roll, traction) may be viewed as potentially deleterious.

For example, during a squat the femoral head is compressed into the acetabulum by muscular forces, bodyweight and any additional external load.

<strong>Concave (Concavity)</strong> - Having an outline or surface curved like the interior surface of a bowl or sphere - to cave-in or curve inward.
<ul>
 	<li>Example, the internal surfaces of the pelvis is concave, holding some of the bodies viscera.</li>
</ul>

<strong>Concordant Sign</strong> - The patient's specific pain, symptom or complaint.<span style="color: #ff0000;"> </span>
<ul>
 	<li>One common error made during evaluation with special tests is attention given to any discomfort or pain, rather than attempting to identify the pain/discomfort related to the patient's complaint (concordant/comparable sign). Many special tests purposefully test tissue limits and are at least mildly uncomfortable in every individual. Basing your assessment on positive tests that resulted in "concordant/comparable signs" will improve your chances of arriving at the correct diagnosis.</li>
</ul>

<strong>Conductivity</strong>: Stimulation results in more than a local effect (1).
<ul>
 	<li>For example, in a muscle cell the stimulation of a motor endplate results in a change in cell membrane polarity that rapidly propagates (is conducted) along the entire length of the muscle cell, stimulating all sacromere.</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

A condyloid joint (also called condylar, bicondylar, ellipsoid, or ellipsoidal) is an ovoid articular surface, or condyle, that is received into an elliptical cavity.  These joints permit movement in two planes.  Examples include the knee, metacarpophalangeal joints and metatarsophalangeal joints.

Connective Tissue Cell - One of the four basic types of animal tissue, consisting mostly fibers and ground substance.  These cells are specialized to binds organs together, holds them in place, protect them from external forces, and may fill space in the body's cavities.

Example, the body's muscles are enclosed in durable connective tissue sheets known as the "epimysium", "perimysium", and "endomysium," which and in support and transmitting force.
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

<strong>Contractility: </strong>The ability to shorten (1).
<ul>
 	<li><strong>Contractility</strong>: Muscle cells are unique in the amount they can shorten when stimulated; this is this largerly due to the highly organized and unique arrangement of myofilaments (actin and myosin).</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

Pertaining to the opposite side

Example, the external oblique muscle performs contralateral rotation; rotation to the opposite side.

<strong>Convex (Convexity)</strong> - Having an outline or surface curved like the exterior of a circle or sphere - to bulge or curve outward.
<ul>
 	<li>Example, the top of your head is shaped by the convex exterior surface of your skull.</li>
</ul>

<strong>Correlational Research</strong> - Non-experimental <a href="https://www.questionpro.com/blog/what-is-research/">research</a> method in which the statistical relationship between two variables is investigated.
<ul>
 	<li>In this research by Kwon et al., a correlation was noted between a decrease in extensibility during a hamstring length test (goniometry) and current knee pain (1).</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/knee/correlation-patellofemoral-pain-syndrome-pfps-hamstring-activity/" target="_blank" rel="noopener">Kwon O, Yun M, and Lee W. (2014). Correlation between intrinsic patellofemoral pain syndrome in young adults and lower extremity biomechanics. <em>J. Phys. Ther. Sci. </em>26: 961-964</a></li>
</ol>

<strong>Counter-nutation</strong> - posterior rotation of sacrum relative to ilium, and/or anterior rotation of ilium relative to sacrum.
<ul>
 	<li>The pelvic floor muscles are examples of muscle that may counter-nutate the sacrum.</li>
</ul>
[caption id="attachment_126335" align="aligncenter" width="400"]<a href="https://brentbrookbush.com/wp-content/uploads/2018/10/Nutation.png"><img class=" wp-image-126335" src="https://brentbrookbush.com/wp-content/uploads/2018/10/Nutation.png" alt="Nutation and Counter-nutation of the Sacroiliac Joint" width="400" height="967" /></a> Nutation and Counter-nutation of the Sacroiliac Joint[/caption]

&nbsp;

<strong>Crossover (Study) Design</strong> - A type of longitudinal, repeated measures quasi-experimental design in which each group receives both treatments, but at different times. It is named "crossover" due to the patients "crossing-over" to the other treatment or sham group after a specified period of time.
<ul>
 	<li>This type of study has the advantage of every individual serving as their own control, which may reduce the influence of confounding variables.</li>
 	<li>Unfortunately, the design itself introduces the chances that anyone receiving the experimental variable in the first period will continue to be effected in the second period.</li>
</ul>
In a study by Senna et al., a cross-over design was used to investigate the difference load made on inter-set rest intervals (1).
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/strength-training-research-corner/heavy-vs-light-load-single-joint-exercise-performance-with-different-rest-periods/" target="_blank" rel="noopener">Senna, G.W., Rodrigues, B.M., Sandy, Scudese, Bianco, A, &amp; Dantas, E.H.M. (2017). Heavy vs light load single-joint exercise performance with different intervals. <em>Journal of Human Kinetics, 58, 197-206.</em> </a></li>
</ol>

Cross-sectional Study - a research design that involves gathering data from a population or representative subset at a specific point in time.
<ul>
 	<li>Example, the study by Karimi-Mobarake et al.(1) investigated the prevalence of genu varum and genu valgum among school children 7-11 years old in Iran.</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/knee/low-prevalence-of-genu-varum-and-valgum-among-elementary-school-children/" target="_blank" rel="noopener noreferrer">Karimi-Mobarake, M., Kashefipour, A., Yousfnejad, Z. The prevalence of genu varum and genu valgum in primary school children in Iran 2003-2004. (2005) <em>Journal of Medical Science</em> 5(1). 52-54</a></li>
</ol>

<strong>Cytokine</strong> - A broad and loose category of small proteins that act through receptors, and are especially important to immune function (inflammation).
<ul>
 	<li>Cytokines include substances such as interferon, interleukin, and growth factors, which are secreted by certain cells of the immune system and have an effect on other cells. Their definite distinction from hormones is a topic of continued research.</li>
</ul>
&nbsp;

Dependent variable - in research, this is the variable that is changed by the independent variable, most often this is the "outcome" of the study.
<ul>
 	<li>Example, in the study by Cleland et al. (1), the independent variable is "thoracic manipulation," and the dependent variable is "lower trapezius muscle strength."</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/short-term-effects-lower-thoracic-manipulation-lower-trapezius-muscle-strength/" target="_blank" rel="noopener noreferrer">Cleland J, Selleck B, Stowell T, Brown L, Alberini S, St. Cyr H, Caron T. Short-term Effects of Thoracic Manipulation on Lower Trapezius Muscle Strength. <em> Journal of Manual &amp; Manipulative Therapy</em>. 2004; 12(2): 82-90</a></li>
</ol>

An anatomical direction; further from the trunk or center of the body

Example, the foot is at the <em>distal</em> end of the leg.

An arthrokinematic motion - a <span class="_Tgc">force applied to a body part that may result in the separation of joint surfaces, a reduction in intra-articular pressure, and/or an increase in intra-articlar space.</span>

For example, to hang from one's hands (i.g. in preparation for a pull-up) results in a traction force on the glenohumeral joint (shoulder).

An anatomical term of location; back or upper surface

Example, shoe laces may compress tissues on the <em>dorsal</em> surface of the foot

The "drawing-in" maneuver is a common cue used during exercise and rehabilitation programs. A light contraction of the <a href="https://brentbrookbush.com/articles/muscular-anatomy/transverse-abdominis/" target="_blank" rel="noopener">transverse abominis</a> (and potentially the entire <a href="https://brentbrookbush.com/articles/corrective-exercise-articles/core-subsystems/intrinsic-stabilization-subsystem/" target="_blank" rel="noopener">intrinsic stabilization subsystem</a>) achieved by gently pulling the lower abdominal region away from one's waist band. This should have minimal effect on breathing, and should not be confused with a maximal contraction of the <a href="https://brentbrookbush.com/articles/muscular-anatomy/transverse-abdominis/" target="_blank" rel="noopener">transverse abdominis</a> resulting in a "vacuum pose".
<ul>
 	<li>Research often refers to this maneuver as the "abdominal drawing-in maneuver"; abbreviated ADIM.</li>
</ul>
Development and introduction of this cue into practice is based on the pivotal research and resulting text:
<ol>
 	<li>Carolyn Richardson, Paul Hodges, Julie Hides. Therapeutic Exercise for Lumbo Pelvic Stabilization – A Motor Control Approach for the Treatment and Prevention of Low Back Pain: 2nd Edition (c) Elsevier Limited, 2004</li>
</ol>

Faulty or abnormal movement; an<span class="_Tgc"> alteration of normal kinematics.</span>

For example, joint stiffness or a reduction in arthrokinematics motion that results in limited osteokinematic range of motion - inadequate inferior glide of the femoral head resulting in limited abduction of the hip.

The seeping into, or abnormal collection of fluid in a body cavity.

For example, knee effusion describes swelling within the knee joint.

Note: the word "effusion" is used differently in medicine than it is used in reference to the movement (seeping out) of liquids and gases, for example in chemistry.

&nbsp;

A trait of body tissues that allows a tissue to return to its resting length or state after deformation or stretch.
Example:  Muscle is elastic tissue; many muscles will return to their resting length after being stretched to 150% of that length without any appreciable change in tissue quality.

<strong>Elasticity</strong>: Elasticity refers to the ability of a cell to return to its resting length after being stretched/lengthened.
<ul>
 	<li>Note: this term is often confused with extensibility. Elasticity is not the ability to stretch; it is the ability to return to normal length after being stretched. Muscle tissue, connective tissue and even nerve tissue have varying levels of elasticity.</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

Epithelial cell - One of the four basic cell types, found lining the body's cavities, blood vessels, organs and constitutes most gland tissue.  These cells are specialized to aid with absorption, secretion, or act as a barrier from foreign objects.
<ol>
 	<li>Saladin, K. S., &amp; Miller, L. (1998). <i>Anatomy &amp; physiology</i>. New York (NY): WCB/McGraw-Hill.</li>
</ol>

<strong>Equilibrium</strong> - a state in which opposing forces or influences are balanced.
<ul>
 	<li>For example, to maintain a neutral trunk while pushing or pulling a weight in one hand, your core musculature must balance the force by creating an equal amount of force in the opposite direction.</li>
</ul>

The study of causation, or origination. The word is commonly used in the medical professions, where it may refer to the study of why things occur, or the reason behind why things act a certain way.

For example, the etiology of low back pain is a complex subject, with multiple contributing factors and various structures implicated.

<div class="gs_citr" tabindex="0"><strong>Evidence-based medicine (practice)</strong> is the integration of best research evidence with clinical expertise and patient(client) values (2)."</div>
<ul>
 	<li class="gs_citr" tabindex="0">...the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients (clients).  It involves the integration of at least (a) clinical expertise/expert opinion, (b) external scientific evidence, and (c) client/patient/caregiver perspectives to provide high-quality services reflecting the interests, values, needs, and choices of the individuals we serve (1).</li>
</ul>
&nbsp;
<ol>
 	<li id="gs_cit1" class="gs_citr" tabindex="0">Sackett, D. L., Rosenberg, W. M., Gray, J. M., Haynes, R. B., &amp; Richardson, W. S. (1996). Evidence based medicine: what it is and what it isn't. <i>Bmj</i>, <i>312</i>(7023), 71-72.</li>
 	<li class="gs_citr" tabindex="0">Sackett D et al. Evidence-Based Medicine: How to Practice and Teach EBM, 2nd edition. Churchill Livingstone, Edinburgh, 2000, p.1</li>
</ol>

<strong>Excitability:</strong> The ability of a cell to <span class="hvr">change</span> in <span class="hvr">membrane</span> <span class="hvr">conductance</span> as a <span class="hvr">response</span> to <span class="hvr">stimulation.
</span>
<ul>
 	<li><span class="hvr">For example, muscle cells are specialized to react to a change in membrane potential with contraction, where as nerve cells are specialized to propagate a change in membrane potential along there axons and communicate that message to other tissues via neurotransmitters.
</span></li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

<strong>Excitation threshold:</strong> The level that a depolarization must reach for an action potential to occur.
<ul>
 	<li>The excitation threshold is a contributing factor to the "all-or-none" response of muscle and nerves cells to a stimulus.</li>
</ul>

<strong>Exercise Progression</strong> - Modification of an exercise with the intent of promoting adaptation by increasing demand. This can be accomplished by increasing reps, load, tempo, range of motion, complexity, and/or challenge to an individual's stability.
<ul>
 	<li>Because load, reps, tempo and complexity are often explicitly noted, the term "exercise progression" is most often used throughout Brookbush Institute (BI) content to refer to an exercise, or series of exercises that make it harder to maintain stability with good form.
<ul>
 	<li>Sample Exercise Progression: <a href="https://brentbrookbush.com/vimeo_videos/kneeling-chop-pattern/" target="_blank" rel="noopener">Kneeling Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/static-standing-chop-pattern/" target="_blank" rel="noopener">Standing Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/single-leg-chop-pattern/" target="_blank" rel="noopener">Single-leg Chop</a></li>
</ul>
</li>
</ul>

<strong>Exercise regression</strong> - The opposite of progression; that is, modification of an exercise with the intent of reducing demand. This can be accomplished by decreasing reps, load, tempo, range of motion, complexity, and/or challenge to an individual's stability. Generally, regressions are used to modify an exercise to the client's current level of ability, with the intent of improving form, motor learning and retention.
<ul>
 	<li>Because load, reps, tempo and complexity are often explicitly noted, the term "exercise regression" is most often used throughout Brookbush Institute (BI) content to refer to an exercise or series of exercises that make it easier to maintain stability with good form.
<ul>
 	<li>Sample Exercise Regression: <a href="https://brentbrookbush.com/vimeo_videos/single-leg-chop-pattern/" target="_blank" rel="noopener">Single-leg Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/static-standing-chop-pattern/" target="_blank" rel="noopener">Standing Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/kneeling-chop-pattern/" target="_blank" rel="noopener">Kneeling Chop</a></li>
</ul>
</li>
</ul>

<strong>Experimental Research</strong> - Studies in which the researchers introduce the variable to be studied, with the intent of observing the outcome. This is different than observational research which observes the effect of a variable already present. Many texts also assert that experimental research should include randomization and ideally a control group, as is seen in Randomized Control Trials. Studies in which the variable is introduced by the researchers, but participants are not randomized may be considered Quasi-experimental research.
<ul>
 	<li>In this study by Esformes, the experimental variable was squat depth and the outcome measures observed were various performance measures related to power (1).</li>
</ul>
<ol>
 	<li><a href="https://brookbushinstitute.com/article/back-squat-depth-lower-body-post-activation-potentiation/" target="_blank" rel="noopener">Esformes, J., &amp; Bampouras, T. (2013). Effect of back squat depth on lower-body postactivation potentiation. <em>Journal of Strength and Conditioning Research, 27</em>(11), 2997-3000.</a></li>
</ol>
&nbsp;

<strong>Extensibility</strong>: The ability of a cell to be stretched or lengthened without damage (1).
<ul>
 	<li>For example, most cells would rupture with even a modest stretch, but muscles can stretch up to 3 times their contracted length.</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

<strong>False Negative </strong>- the proportion of negatives in a group that were assessed incorrectly (assessed as negative when the patient was actually positive)
<ul>
 	<li>Test Results: Although most tests/assessments result in either a positive or negative, the accuracy of a test is dependent on the number  of positives and negatives that are correct. Therefore, when the accuracy of a test is determined, their are 4 possible results, because a positive or negative result could be right (true) or wrong (false).</li>
</ul>

<strong>False Positive </strong>- the proportion of positives in a group that were assessed incorrectly (assessed as positive when the patient was actually negative)
<ul>
 	<li>Test Results: Although most tests/assessments result in either a positive or negative, the accuracy of a test is dependent on the number  of positives and negatives that are correct. Therefore, when the accuracy of a test is determined, their are 4 possible results, because a positive or negative result could be right (true) or wrong (false).</li>
</ul>

The function of fascia is to transmit force, provide support, and protect tissues. Fascia can effect motion by:
Transmitting force from one or more muscles (example: the thoracolumbar fascia)
Restricting motion in cases of adaptive shortening and/or adhesion to proximal structures (example: iliotibial band in cases of lower-leg dysfunction)
Elastic recoil after stretching can contribute to force production (example: plyometric exercise)

Note: There is evidence that fascia may house more receptors related to human movement than other tissues. In this way fascia may act as a motherboard for the nervous system

The fascial system does not contract or develop trigger points, and its capacity to adapt to stretching and or strengthening exercise is limited, especially when compared to the adaptive capacity of muscle tissue.

<strong>Fibromyalgia</strong> - A loosely defined diagnosis that is associated with a combination of widespread pain <i>in combination with</i> 2) tenderness at 11 or more of the 18 specific tender point sites. Consideration may also be given to the presence of psychosocial stressors and inflammatory disease in the patients history. Newer research suggests that fibromyalgia may be at least in part due to central sensitization of myofascial pain, often associated with trigger points (1 - 4).
<ol>
 	<li>Wolfe, F. (2018). Fibromyalgia Syndrome and Fibromyalgia Syndrome Criteria: Problems in Definition and Validity. <i>Fibromyalgia Syndrome and Widespread Pain: From Construction to Relevant Recognition</i>.</li>
 	<li>Wolfe, F., Smythe, H. A., Yunus, M. B., Bennett, R. M., Bombardier, C., Goldenberg, D. L., ... &amp; Fam, A. G. (1990). The American College of Rheumatology 1990 criteria for the classification of fibromyalgia. <i>Arthritis &amp; Rheumatism: Official Journal of the American College of Rheumatology</i>, <i>33</i>(2), 160-172.</li>
 	<li>Alonso-Blanco, C., Fernandez-de-las-Penas, C., Morales-Cabezas, M., Zarco-Moreno, P., Ge, H. Y., &amp; Florez-García, M. (2011). Multiple active myofascial trigger points reproduce the overall spontaneous pain pattern in women with fibromyalgia and are related to widespread mechanical hypersensitivity. <i>The Clinical journal of pain</i>, <i>27</i>(5), 405-413.</li>
 	<li>Staud, R., Nagel, S., Robinson, M. E., &amp; Price, D. D. (2009). Enhanced central pain processing of fibromyalgia patients is maintained by muscle afferent input: a randomized, double-blind, placebo-controlled study. <i>PAIN®</i>, <i>145</i>(1-2), 96-104.</li>
</ol>
&nbsp;

Muscles that act to reduce or prevent movement at proximal joints to improve force transmission.
Example: The muscles of the core are important fixators; reducing motion of the spine/trunk to enhance force transmission between the extremities and environment.

An increase in joint stability via compressive forces resulting from muscular contraction and increased tension in fascial structures (1,2).
<ul>
 	<li>This term is most often used in reference to core intrinsic stabilizers, the thoracolumbar fascia and the sacroiliac joint; however, force closure and form closure have been mentioned in the literature referring to other joints.</li>
 	<li>Related term: Form closure</li>
</ul>
<ol>
 	<li>Andry Vleeming, Vert Mooney, Rob Stoeckart. Movement, Stability &amp; Lumbopelvic Pain: <a class="glossaryLink " title="Glossary: Integration" href="https://brentbrookbush.com/glossary/integration/" target="_blank" rel="noopener noreferrer" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Integration&lt;/div&gt;&lt;div class=glossaryItemBody&gt;Making a whole of parts.&lt;br /&gt;&lt;br /&gt;Example, The Brookbush Institute uses an integrative approach to explaining and addressing human movement.&lt;/div&gt;">Integration</a> of Research and Therapy. (c) 2007 Elsevier Limited</li>
 	<li id="gs_cit1" class="gs_citr" tabindex="0">Vleeming, A., Pool-Goudzwaard, A. L., Stoeckart, R., van Wingerden, J. P., &amp; Snijders, C. J. (1995). The Posterior Layer of the Thoracolumbar Fascia| Its Function in Load Transfer From Spine to Legs. <i>Spine</i>, <i>20</i>(7), 753-758.</li>
</ol>

The relative contribution of joint shape and structure to the stability of a joint (1,2).
<ul>
 	<li>This term is most often used in reference to the "rough" articulating surfaces of the sacroiliac joint and the wedge shape of the sacrum; however, force closure and form closure have been mentioned in the literature referring to other joints.</li>
 	<li>Related term: Force closure</li>
</ul>
<ol>
 	<li>Andry Vleeming, Vert Mooney, Rob Stoeckart. Movement, Stability &amp; Lumbopelvic Pain: <a class="glossaryLink " title="Glossary: Integration" href="https://brentbrookbush.com/glossary/integration/" target="_blank" rel="noopener noreferrer" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Integration&lt;/div&gt;&lt;div class=glossaryItemBody&gt;Making a whole of parts.&lt;br /&gt;&lt;br /&gt;Example, The Brookbush Institute uses an integrative approach to explaining and addressing human movement.&lt;/div&gt;">Integration</a> of Research and Therapy. (c) 2007 Elsevier Limited</li>
 	<li id="gs_cit1" class="gs_citr" tabindex="0">Vleeming, A., Pool-Goudzwaard, A. L., Stoeckart, R., van Wingerden, J. P., &amp; Snijders, C. J. (1995). The Posterior Layer of the Thoracolumbar Fascia| Its Function in Load Transfer From Spine to Legs. <i>Spine</i>, <i>20</i>(7), 753-758.</li>
</ol>

An arthrokinematic motion - linear motion across a joint surface parallel to the plane of the adjacent joint surface, just as your posterior moves relative to a "slide" in a park.

For example, the glide of facet joint in the spine during spinal flexion and extension, or the posterior glide of the humeral head that must accompany anterior roll to maintain congruence with glenoid fossa during shoulder horizontal adduction.

A plane joint (also called an arthrodial joint, gliding joint or plane articulation) is a synovial joint which allows only gliding movement in the plane of the articular surfaces. The opposed surfaces of the bones are flat or almost flat, with movement generally limited by tight capsules and ligaments. Plane joints are numerous, are most often small, and allow very little motion.  Examples include the carpal joints of the wrist, the tarsal joints of the ankle, and the facet joints of the spine.

"...refers to the measurement of angles, in particular the measurement of angles created at human joints by the bones of the body (1).

&nbsp;
<ol>
 	<li>Cynthia C. Norkin, D. Joyce White. Measurement of Joint Motion: A Guide to Goniometry 3rd Edition. Copyright (C) 2003 by F.A. Davis Company</li>
</ol>

Ground reaction force (GRF) - The force exerted by the ground on the body in contact with it.

For example, when a runner's foot strikes the ground with a force equal to the mass of the individual times their acceleration due to gravity, momentum and muscular exertion, the ground exerts an equal and opposite force on the runner's foot.
<ul>
 	<li>GRF is often measured in research studies using force plates as a means of quantitatively measuring the force generated by an individual.</li>
</ul>

<strong>H-Band</strong> - Refers to the central zone of a sarcomere that looks lighter under a microscope.  This area of the sarcomere is a lighter portion of the A-band where there is no overlap between the thinner filaments (actin), and the thicker filaments (myosin).
<ul>
 	<li>Example, when a muscle contracts, actin and myosin cross-bridging occurs in the region of the A-band until the H-band is reached where no overlap occurs.</li>
</ul>
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

A hinge joint (also called a ginglymus) is a synovial joint in which the articular surfaces fit one another in a way that only permits motion in one plane. Examples include the elbow, the knee (unless considered a condyloid joint) and the interphalangeal joints.

Holism (holistic) (<em>biological holism</em>) - (from Greek <i>holos</i> "all, whole, entire") is the idea that systems and their properties should be viewed as wholes, not just as a collection of parts.
<ul>
 	<li>Summarized by Aristotle in his "Metaphysics": "The whole is more than the sum of its parts". However, the term "holism" was introduced into language by the South African statesman Jan Smuts as recently as 1926. (Smuts J. C. 1987 [1926]. <em class="EmphasisTypeItalic ">Holism and evolution</em>. Cape Town: N &amp; S Press.)</li>
</ul>
Example: The Brookbush Institute promotes a holistic approach to human movement science, in which the muscular, fascial, articular and neural systems are not viewed as separable and all proximal segments are considered.

<strong>Hormone: </strong>Chemical messengers produced by the endocrine system, transported via tissue fluids such as blood, to stimulate cells to "act."
<ul>
 	<li>Example: Growth hormone is secreted by the pituitary gland in the brain; stimulating growth, cell reproduction and cell regeneration in certain types of cells</li>
</ul>
The English physician E. H. Starling discovered in collaboration with the physiologist W. M. Bayliss secretin, the first hormone, in 1902. (1).
<ol>
 	<li>Henriksen, J. H., &amp; de Muckadell, O. S. (2000). Secretin, its discovery, and the introduction of the hormone concept. <i>Scandinavian journal of clinical and laboratory investigation</i>, <i>60</i>(6), 463-472.</li>
</ol>

A range of motion achieved by the patient/client that is more than normal.
<ul>
 	<li>Note: Both hyper-mobility and hypo-mobility may adversely affect motion and may lead to deleterious effects on joints and soft tissue over time. There is no evidence to suggest that more or less flexibility than normal is beneficial.</li>
</ul>
Example: If an individual can place their forehead on their knees they are likely hypermobile at one, if not several joints

Example 2: 110° of shoulder external rotation would be considered hyper-mobile.

<strong>Hyperplasia</strong> is an increase in organic tissue size due to an adaptive increase in the number of cells per organ.
<ul>
 	<li>Although muscle hyperplasia has been noted in some animals, human muscle tissue does not seem to have this adaptive ability.</li>
</ul>

A condition of excessive tone of the skeletal muscles; increased resistance of muscle to passive stretching.  May be related to increased neural drive, synergistic dominance, trigger points, reflexive over-activity, and/or muscle length.
Example:  Individuals who exhibit ankle eversion and abduction during an overhead squat assessment likely have hypertonic fibularis (peroneal) muscles.

<strong>Muscular hypertrophy</strong> is an increase in muscle mass/size due to increase in the volume and cross-sectional area (CSA) of individual muscle cells. The increase in cross-sectional area can be attributed to an an increase in contractile proteins and structural elements (myofibrillar hypertophy), as well as an increase in glycogen storage and elements related to metabolism (sarcoplasmic hypertophy). Hypertrophy is an adaptation of both cardiac and skeletal muscle fibers in response to progressive increases in workload.
<ul>
 	<li>Note: Hypertrophy is not hyperplasia. Hyperplasia is an increase in muscle size due to an adaptive increase in the number of muscle fibers/cells per muscle. This type of adaptation does not occur in human muscle tissue.</li>
</ul>

A range of motion achieved by a patient/client that is less than normal.
<ul>
 	<li>Note: Both hyper-mobility and hypo-mobility may adversely affect motion and may lead to deleterious effects on joints and soft tissue over time. There is no evidence to suggest that more or less flexibility than normal is beneficial.</li>
</ul>
Example: If the end range of shoulder external rotation is reached and measured as 75° during goniometric assessment, the client/patient is exhibiting hypomobility of the glenohumeral joint (shoulder).

Hypothesis - a proposed explanation for a phenomenon; "scientific hypotheses" are generally constructed in a way that is testable or falsifiable.
<ul>
 	<li>Example: The hypothesis, "excessive knee valgus may be correlated with future knee pain and injury," has been the subject of several studies published over the last decade.</li>
</ul>

Diminished tone of skeletal muscles; diminished resistance of muscles to passive stretching.   May be related to inhibition, reciprocal inhibition, arthrokinematics inhibition and/or  increased resting length of muscle.
Example:  If your knees cave (hip adduction) during a squat or leg-press it is likely that your gluteus medius is hypotonic.

<strong>I-Band</strong> - Refers to the part of the muscle cell that looks lighter under a microscope.  This area of the cell is lighter due to parallel arrangement of thinner filaments (actin), and no overlap with the thicker filaments (myosin).
<ul>
 	<li>As a muscle contracts, the I-bands will decrease in width and move closer to one another.</li>
</ul>
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

Independent variable - in research, this is the variable or phenomenon being manipulated in the study.
<ul>
 	<li>Example, in the study by Ghanbari et al. (1), the independent variable is "knee joint mobilization", the dependent variable is "quadriceps muscle strength."</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/effect-knee-joint-mobilization-quadriceps-muscle-strength/" target="_blank" rel="noopener noreferrer">Ghanbari A. and Kamalgharibi S. (2013). Effect of knee joint mobilization on quadriceps muscle strength. <em>International Journal of Health and Rehabilitation Sciences</em>. 2(4): 186-191</a></li>
</ol>

An anatomical direction; toward the bottom (below)

Example, the mouth is <em>inferior</em> to the eyes

A reduction in neural drive, muscular activity, and or force output due to altered neuromuscular reflex.  Alterations in neuromuscular reflex may occur due to increases in muscle length (hypothesis: increased excitation threshold), altered reciprocal inhibition in response to increased antagonist tone, and or alterations in joint motion (arthrokinematics inhibition).

Making a whole of parts.

Example, The Brookbush Institute uses an integrative approach to explaining and addressing human movement.

<strong>Intermuscular Coordination</strong> - Optimal timing and motor unit recruitment of agonists, antagonists, synergists, neutralizers, stabilizers and fixators.

<strong>Example: Role of Muscles during Hip Extension</strong>
<ul>
 	<li><strong><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Prime Mover" href="https://brentbrookbush.com/glossary/prime-mover/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Prime Mover&lt;/div&gt;The muscle most responsible for a joint action under load -&lt;br /&gt;&lt;br /&gt;That is, the muscle that can produce the most force for a given joint action. Often this term is used synonymously with the term agonist. The prime mover as defined above, may or may not be the most active muscle for a joint action during activities of daily living.&lt;br /&gt;&lt;br /&gt;Example: the gluteus maximus is the most powerful hip extensor and therefore the prime mover; however, the hamstrings are likely the most active hip extensors during low level activities like walking or standing.">Prime Mover</a>:</strong>  <a href="https://player.vimeo.com/external/82855344.hd.mp4?s=54c3e7d98fb9d4e0af8d282c85ba9b3e">Gluteus maximus</a></li>
 	<li><strong><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Synergists" href="https://brentbrookbush.com/glossary/synergists/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Synergists&lt;/div&gt;Muscles that assist the prime mover in performing a joint action.&lt;br /&gt;&lt;br /&gt;That is, all muscles that can perform a joint action that are not the prime mover, are termed synergists.&lt;br /&gt;Example: The rectus abdominis is the prime mover of spinal flexion. All other muscles that can perform spinal flexion are synergists including – external obliques, internal obliques and psoas.">Synergists</a>:</strong> <a href="https://brentbrookbush.com/articles/muscular-anatomy/biceps-femoris/">Biceps femoris (long head)</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/semitendinosus-and-semimembranosus/">semitendinosus, semimembranosus</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/adductors/">posterior head of adductor magnus</a></li>
 	<li><strong><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Antagonist" href="https://brentbrookbush.com/glossary/antagonists/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Antagonist&lt;/div&gt;Muscles that oppose the prime mover and synergists for a given joint action.&lt;br /&gt;&lt;br /&gt;That is, all the muscles that can perform the opposing joint action.&lt;br /&gt;&lt;br /&gt;Example: The triceps and anconeus are antagonists during elbow flexion.">Antagonists</a>:</strong> <a href="https://brentbrookbush.com/articles/muscular-anatomy/psoas/">Psoas</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/iliacus/">iliacus</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/tensor-fascia-latae-tfl/">tensor fascia latae</a> (TFL),<a href="https://brentbrookbush.com/articles/muscular-anatomy/rectus-femoris/"> rectus femoris</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/adductors/">anterior adductors (especially pectineus)</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/sartorius/">sartorius</a></li>
 	<li><strong><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Neutralizer" href="https://brentbrookbush.com/glossary/neutralizers/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Neutralizer&lt;/div&gt;Muscles that oppose unwanted joint motions created by the prime mover and/or synergists, and/or muscles that prevent unwanted ancillary motion.&lt;br /&gt;Example: The teres minor and infraspinatus neutralize the internal rotation force created by the pectoralis major during horizontal adduction of the shoulder.">Neutralizers</a>:</strong> <a href="https://brentbrookbush.com/articles/muscular-anatomy/gluteus-minimus/">Gluteus minimus</a> and <a href="https://brentbrookbush.com/articles/muscular-anatomy/gluteus-medius/">anterior fibers of gluteus medius</a> neutralize external rotation force of <a href="https://brentbrookbush.com/articles/muscular-anatomy/gluteus-maximus/">gluteus maximus</a></li>
 	<li><strong><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Stabilizer" href="https://brentbrookbush.com/glossary/stabilizers/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Stabilizer&lt;/div&gt;Muscles whose primary role is to improve arthrokinematics by maintaining optimal alignment of joint surfaces.&lt;br /&gt;&lt;br /&gt;Most often these muscles are the most intrinsic muscles of a joint, have a larger percentage of Type I muscle fibers and are rich in proprioceptors.&lt;br /&gt;Example: The muscles of the rotator cuff act as stabilizers for most shoulder motions.">Stabilizers</a>:</strong> <a href="https://brentbrookbush.com/articles/muscular-anatomy/deep-rotators-of-the-hip/">Deep rotators of hip</a></li>
 	<li><strong><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Fixator" href="https://brentbrookbush.com/glossary/fixators/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Fixator&lt;/div&gt;Muscles that act to reduce or prevent movement at proximal joints to improve force transmission.&lt;br /&gt;Example: The muscles of the core are important fixators; reducing motion of the spine/trunk to enhance force transmission between the extremities and environment.">Fixators</a>: </strong><a href="https://brentbrookbush.com/articles/core-subsystems/intrinsic-stabilization-subsystem/">Intrinsic stabilization subsystem</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/rectus-abdominis/">rectus abdominis</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/internal-obliques/">internal</a> and <a href="https://brentbrookbush.com/articles/muscular-anatomy/external-obliques/">external obliques</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/quadratus-lumborum/">quadratus lumborum</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/erector-spinae/">erector spinae</a></li>
</ul>
&nbsp;

Example from: <a href="https://brentbrookbush.com/articles/anatomy-articles/introduction-to-functional-anatomy/kinesiology-of-the-hip/" target="_blank" rel="noopener">Introduction to Functional Anatomy: Kinesiology of the Hip</a>

Intramuscular coordination refers to the coordinated recruitment of motor units within a single muscle. This concept is used to explain increases in maximal strength and power; however, the coordinated and sequential recruitment of motor units is also essential to strength endurance and smooth coordinated motion.  Related terminology may include; motor unit recruitment, preferential recruitment, rate coding, sequence, etc..

Example: It is hypothesized that the "shaking" noted during a novice exercisers attempt at an activity like the <a href="https://brentbrookbush.com/vimeo_videos/ball-crunch-and-progressions/" target="_blank">stability ball crunch</a> may be due to relatively poor intramuscular coordination. Rather than smooth, sequential firing of rectus abdominis motor units, groups of motor units turn on and off in an uncoordinated manner.

Pertaining to the same side

Example, the quadratus lumborum performs ipsilateral flexion; lateral flexion toward the same side as the muscle.

An <strong>isoform</strong>, or variant, is a member of a set of similar proteins, that originate from the same gene, or gene family.<sup id="cite_ref-2" class="reference"></sup>
<ul>
 	<li>Example, the variations in myosin heavy chain proteins (MHC I, MHC IIA, MHC IIB/X) that contribute to the characteristic differences between muscle fiber types.</li>
</ul>

“The Prime Assumption”
Everything crossing a joint will influence joint motion during every joint action.

A concept that has expanded over the past several decades to describe the integration of 4 body systems (muscle, joints, fascia and nerves), as well as, the coordinated function of various body segments (e.g. hip, knee and ankle) to produce motion. Kinetic referring to motion, and chain being an analogy for the interdependent link between systems.

Example, the posterior <em>kinetic chain</em>, refers to the integrated function of nerves, muscles, fascia and joints on the posterior side of the body.

The concept of the kinetic chain was originally adapted from the work of a mechanical engineer named Franz Reuleaux (Kinematics of Machinery (1875)) by Dr. Arthur Steindler in 1955 (Steindler A: Kinesiology of the Human Body. Springfield, IL, Charles C. Thomas Co.. 1955).

<strong>Latent Trigger Point</strong> - A myofascial trigger point that is not painful at rest, only painful when palpated, and may or may not exhibit a characteristic referral pain pattern when palpated.  Latent trigger points do result in an acute point of sensitivity, in a taut band of muscle, and may restrict range of motion (1).

Note: Based on the clinical experience, the Brookbush Institute suggests that latent trigger points (sometimes refereed to as Tender Points) are more common than active trigger points. Further, they are likely addressed more often than trigger points; being the intended target of many soft-tissue mobility techniques.
<ol>
 	<li>David G. Simons, Janet Travell, Lois S. Simons, <em>Travell &amp; Simmons’ Myofascial Pain and Dysfunction, The Trigger Point Manual, Volume 1. Upper Half of Body: Second Edition</em>,© 1999 Williams and Wilkens</li>
</ol>

An anatomical direction; further from the midline

Example, the anterior deltoid is <em>lateral</em> to the pectoralis major

<strong>Length/Tension Relationship</strong> - The amount of force generated by a muscle is dependent on sarcomere length.
<ul>
 	<li>The ability of sarcomere to maximally produce force occurs when sarcomere length results in optimal overlap between actin and myosin. Stretching a sarcomere decreases overlap between actin and myosin filaments and reduces force production (1-3). When length is less than optimal, actin from opposite ends overlap and interfere with cross-bridging, and myosin filament are compressed as they contact the the Z-disk also reducing force (4)</li>
</ul>
<ol>
 	<li>Gordon, A. M., Huxley, A. F., &amp; Julian, F. J. (1966). The variation in isometric tension with sarcomere length in vertebrate muscle fibres. <i>The Journal of physiology</i>, <i>184</i>(1), 170-192.</li>
 	<li>Edman, K. A. P. (1966). The relation between sarcomere length and active tension in isolated semitendinosus fibres of the frog. <i>The Journal of Physiology</i>, <i>183</i>(2), 407-417.</li>
 	<li>Lieber, R. L., Loren, G. J., &amp; Friden, J. (1994). In vivo measurement of human wrist extensor muscle sarcomere length changes. <i>Journal of neurophysiology</i>, <i>71</i>(3), 874-881.</li>
 	<li>Lieber, R. L. (2002). <i>Skeletal muscle structure, function, and plasticity</i>. Lippincott Williams &amp; Wilkins.</li>
</ol>
&nbsp;

<span class="_Tgc"><strong>Levels of Evidence</strong> - Relative to evidence-based practice, levels of evidence are an attempt to describe the strength of the results measured in a clinical trial or research study.  Note: levels of evidence do not supersede the critical evaluation of an experienced professional, and should be viewed as guidelines - a meta-analysis may be poorly constructed (Level IA), and a comparative study (Level III) may employ new technologies and a strong methodology.
</span>

The Levels of Evidence used by the Brookbush Institute, as described by Shekelle et al.(1):
<ul>
 	<li class="p1">IA - Evidence from meta-analysis of randomized controlled trials</li>
 	<li class="p1">IB - Evidence from at least one randomized controlled trial</li>
 	<li class="p1">IIA - Evidence from at least one controlled study without randomization</li>
 	<li class="p1">IIB - Evidence from at least one other type of quasi-experimental study</li>
 	<li class="p1">III - Evidence from non-experimental descriptive studies, such as comparative studies, correlation studies, and case-control studies</li>
 	<li class="p1">IV - Evidence from expert committee reports or opinions or clinical experience of respected authorities, or both</li>
</ul>
<ol>
 	<li>Shekelle, P. G., Woolf, S. H., Eccles, M., &amp; Grimshaw, J. (1999). Developing clinical guidelines. <i>Western Journal of Medicine</i>, <i>170</i>(6), 348.</li>
</ol>

<strong>Likelihood Ratios</strong> - Likilihood ratios are used for assessing the value of performing a diagnostic test. They use sensitivity and specificity to determine whether a test result usefully changes the practitioner's chance (probability) of reaching the correct assessment. Calculation of likelihood ratios is based on Baye's theorem.
<ul>
 	<li><strong>Positive Likelihood Ratio (LR+)</strong> - The ratio of a positive test result in people with the pathology to a positive test result in people without the pathology.</li>
 	<li><strong>Negative Likelihood Ratio (LR-)</strong> - The ratio of a negative test result in people with the pathology to a negative test result in people without the pathology.</li>
</ul>

Longitudinal Study - a research design that involves observing the same variables, several times over a period of time.
<ul>
 	<li>Example, the study by Hewett et al. (1) is a type of longitudinal study called a "cohort study." This study investigated whether excessive knee valgus during landing was a predictor of knee injury risk in adolescent females over the course of a season.</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/knee/research-review-increased-valgus-during-landing-predicts-acl-injury-in-adolescent-female-athletes/" target="_blank" rel="noopener noreferrer">Hewett, T. E., Myer, G. D., Ford, K. R., Heidt, R. S., Colosimo, A. J., McLean, S. G., &amp; Succop, P. (2005). Biomechanical measures of neuromuscular control and valgus loading of the knee predict anterior cruciate ligament injury risk in female athletes A prospective study. The American journal of sports medicine, 33(4), 492-501</a></li>
</ol>

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Acute Variables: Repetition Range

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