Electromyographic Analysis of the Gluteus Medius and Gluteus Maximus during commonly used Rehabilitation Exercises
By Scott Hoar, DC, CSCS, CEAS, ART, SFMA, FMS
Edited by Brent Brookbush DPT, PT, MS, PES, CES, CSCS, ACSM H/FS
Original Citation: Boren K, Conrey C, Le Coguic J, Paprocki, L,Voight M, Robinson. Electromygraphic Analysis of the Gluteus Medius and Gluteus Maximus during Rehabilitation Exercises. Int J Sports Phys Ther. 2011 Sep; 6(3): 206–223 - FULL TEXT
Images from Original Article - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3201064/bin/ijspt-06-206-f003.jpg
Why is this relevant?: In the past decade, human movement professionals have identified, researched and modified practice to address the importance of proximal stability , strength and control when addressing altered movement patterns of the lower extremity . This study compares 18 commonly used exercise for gluteus medius and gluteus maximus activation . This may provide the practitioner with information that refines exercise selection and optimizes intervention when addressing lower extremity issues.
Study Summary
| Study Design | Observational Study, Crossover Design |
| Level of Evidence | IIA – Evidence from at least one controlled study without randomization |
| Subject Demographics |
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| Outcome Measures | Kinematic data was collected utilizing surface EMG testing of the gluteus medius and gluteus maximus muscle during 18 different exercises. Maximal voluntary isometric contraction (MVIC) was established utilizing side-lying hip abduction as a baseline for both muscles. Mean Electromyographic (MEG) data were analyzed using a root-mean-square algorithm and smoothed with a 50 millisecond time reference. Rank ordering of the exercises was performed utilizing the average percent of MVIC peak activity for each exercise. Muscle Contraction Data was collected by the following methods:
Data was collected for each of the following exercises:
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| Results | The following exercises scored the highest % MVIC for the Gluteus Medius:
The following exercises scored the highest % MVIC for the Gluteus Maximus:
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| Conclusions | The largest recruitment of the gluteus maximus and medius was recorded during the Front Plank with Hip Extension, Side Plank Abduction-Dominant Leg Up, Side Plank Abduction-Dominant Leg Down, and the Single limb Squat. Keep in mind, that exercises must be carefully progressed with the goal of achieving optimal form during those exercises that achieved the highest #MVIC. In this way a clam may be a great exercise for the novice individual, deconditioned individual, or those recovering from an acute injury, with a goal of progressing to plank type exercises. |
| Conclusions of the Researchers | Higher % MVIC values achieved during performance of an exercise correlate with increased muscle hypertrophy. By knowing the % MVIC of the gluteal musculature that occurs during various exercises, potential for strengthening of the gluteal muscle can be inferred. Additionally, exercises may be rank ordered to appropriately challenge the gluteal musculature during rehabilitation of injuries. |
Side Plank and Side Plank with leg Abducted - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3201064/bin/ijspt-06-206-f006.jpg
Review & Commentary:
The exercises with the highest % MVIC were plank type exercises. The researchers suggested that this may be do to co-activation of the core and glute musculature - perhaps reinforcing muscle activation via the recruitment of motor synergies (core subsystems ). Although synergistic recruitment may have played a role, it seems unlikely that this is the primary reason for he relatively drastic differences noted between these and other exercises . It would seem more likely that the increase in % MVIC was the result of greater loads due to longer moment arms and less passive support resulting in greater stress on the glute musculature. For example, although standing exercises recruit a large number of muscles, including core muscles, they did not cause the same drastic increase in % MVIC. This may be explained by the amount of load absorbed by passive structures (bones stacked in opposition to gravity) and the relatively small moment arm between the hip, the bodies center of mass and the greater trochanter. Where as a side plank places a very long moment arm (foot to hip + elbow to hip) in opposition to the gluteus medius and maximus with very little passive support to absorb load.
Other factors and questions raised by this he data in this study include % MVIC when the gluteus medius and maximus are used as stabilizers versus prime movers, whether % MVIC is as important as the selection of exercise that more closely mimics function, and what exercises can maintain a relatively % MVIC without increased recruitment of synergists.
This study had many strengths, including intent. Very few studies compare commonly used exercises in a rehab setting in an attempt to enhance exercise selection. More comparative, practical research is needed. This study did review previous research to build on the finding of similar studies. The exercise selection was built upon those exercises found to have the largest % MVIC in those previous studies. A total of 18 exercises were analyzed, with a minimum of 20 of the 26 subjects contributing to the data compiled on each. Starting with a larger subject pool allowed the researchers freedom to discard data that was marred by EMG lead faults. The analysis of both the gluteus medius and the gluteus maximus also allows the practitioner to make better exercise selections depending on the target muscle; while, being able to note under most circumstances both muscles are recruited together.
This study seemingly had very few weaknesses; however, there are aspects of the research design that leave unanswered questions and a need for further research. The most notable is the use of body weight and no external resistance. As each exercise in this study will result in varied load placed on the gluteus medius and gluteus maximus due to the length of moment arms, mass lifted (upper body versus the weight of a leg versus the weight of leg supported), and support by passive structures (bone on bone contact in standing, versus a side plank with little passive support) it is hard to tell which exercises are in fact "superior" choices and which exercises increased % MVIC due to the load placed on the muscle alone. In a future study, it would be interesting to note the differences in EMG activity between exercises if an attempt is made to equalize loads across all exercises by using a set number of reps, time-under-tension, or MVIC. We may find that a weighted clam 4 is just as beneficial as a side plank. Another area for further research is synergistic recruitment. The researchers noted that some test subjects had complaints of hamstring cramping on the exercise - single leg bridge unstable. By increasing the number of muscles analyzed it may be possible to add another layer of sophistication to exercise selection by not only selecting those exercises with the highest % MVIC, but those with the lowest recruitment of commonly over-active synergists . In essence this build upon the findings of Kan et. al. and Selkowitz et. al. who examined gluteal muscle recruitment compared to biceps femoris and tensor fascia latae (TFL) recruitment in commonly used exercises (1, 2).
Why is this study important?
This study compares commonly used exercises with intent of enhancing exercise selection. The importance of the gluteus maximus and gluteus medius relative to proximal stability , strength and control when addressing altered movement patterns of the lower extremity has been well established. This study may allow the practitioner to enhance exercise selection and improve outcomes.
How does it affect practice?
Although it may be argued that the exercises analyzed in this study would not all be used with the same intent (i.e. activation , core , strengthening , etc.), the comparison of these exercises should aid in refining exercise selection. For example, similar to the Selkowitz et. al. study, this study showed that extension aided in glute recruitment during clams and that internal rotation was not beneficial.
In the case of the plank exercises, this may give clinicians a "goal progression" to attain before discharge, and may influence strength and conditioning coaches/personal trainers to consider the side-plank as an integral part of a core conditioning routine. Further, "glute squeeze" performed well during testing, and this simple cue may be easily added to the practice of any human movement professionals to increase glute activity during any lower extremity exercise.
How does it relate to Brookbush Institute Content?
The Brookbush Institute notes decreased activity and strength in the gluteus medius and gluteus maximus in both the predictive models of Lumbo Pelvic Hip Complex Dysfunction (LPHCD) and Lower Extremity Dysfunction (LED), as well as, the variation of LPHCD - Lumbosacral Dysfunction . Much consideration has been given to gluteus maximus activation and gluteus medius activation in these models, as well as the implications on practice (After all we made shirts that read "GOT GLUTES?"). The side plank , plank and bridge progressions are commonly used progressions for "Core Activation and Strengthening " in the Brookbush Institute model (Rehabilitation and Integrated Warm-Up Templates).
Integrated Warm-Up Template
- Release
- Mobilize
- Lengthen
- Isolated Activation
- Core Activation
- Reactive Activation
- Stability Integration
- Subsystem Integration
Ball Plank Progressions
Side Plank
Gluteus Medius Activation Progressions:
Ball Bridge with Rotation
Bibliography
- Kan, S., Jeon, H., Kwon, O., Cynn, H., Choi, B. (2013). Activation of the gluteus maximus and hamstring muscles during prone hip extension with knee flexion in three hip abduction positions. Manual Therapy 18, 303-307
- Selkowitz, D. M., Beneck, G. J., & Powers, C. M. (2013). Which exercises target the gluteal muscles while minimizing activation of the tensor fascia lata? electromyographic assessment using fine-wire electrodes. journal of orthopaedic & sports physical therapy, 43(2), 54-64 .
© 2015 Brent Brookbush
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