Research Review: Comparison of effects of eccentric training, eccentric-concentric training, and eccentric-concentric training combined with isometric contraction in the treatment of lateral elbow tendinopathy.
By Nate Missler MOT, OTR/L
Edited by Brent Brookbush DPT, PT, COMT, MS, PES, CES, CSCS, ACSM H/FS
Original Citation: Stasinopoulos, D., & Stasinopoulos, I. (2017). Comparison of effects of eccentric training, eccentric-concentric training, and eccentric-concentric training combined with isometric contraction in the treatment of lateral elbow tendinopathy. Journal of Hand Therapy, 30, 13-19. ABSTRACT
Why the Study is Relevant: Lateral elbow tendinopathy (LET), also known as “tennis elbow”, is a common forearm pathology, resulting in localized pain around the lateral epicondyle of the humerus and pain with gripping and/or wrist extension (1). Studies have demonstrated that eccentric exercise may be effective for LET; however, the combined effect of eccentric, concentric and isometric exercise has yet to be studied (2 - 4). This 2016 study by Stasinopoulos et al. compared the effects of eccentric training, eccentric-concentric training, and eccentric-concentric plus isometric wrist extension exercises in participants with LET. The findings suggest that eccentric-concentric training combined with isometric exercise is most effective for addressing symptoms of LET.
Tyler Twist performed by Krystal Salvent with instruction from Dr. Brookbush (c) Brookbush Institute
Study Summary
| Study Design | Randomized Controlled Trial (RCT) |
| Level of Evidence | IB Evidence from at least one randomized controlled trial |
| Participant Characteristics | Number of participants: 34 (19 female, 15 male) Mean age: Approximately 43 years old Inclusion Criteria:
Exclusion Criteria:
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| Methodology | Participants were randomly placed into three groups: Group A: Eccentric training
Participants allowed the wrist to slowly flex for 30 seconds and then returned the wrist to the starting position with the assistance of the un-involved hand. Group B: Eccentric-concentric training
Participants allowed the wrist to slowly flex for 30 seconds and then returned the wrist to the starting position (full extension) with no assistance from un-involved hand. Group C: Eccentric-concentric with isometric training
In each session, participants performed three sets of 15 repetitions, with 1-minute inter-set rest intervals. Participants performed static stretching of the wrist extensors 3 times prior to and after exercise, holding each for 30-45 seconds. The exercise program was performed 5 times a week for 4 weeks. |
| Data Collection and Analysis | Analysis:
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| Outcome Measures | Measured at baseline (Week 0), the end of the program (Week 4) and 1 month after the program (Week 8).
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| Results | ANOVA revealed no significant difference at baseline between groups. At Week 4 and at Week 8, a significant difference in magnitude was recorded between groups, so Bonferroni post hoc tests were performed.
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| Our Conclusions | The findings suggest that although eccentric exercise is effective for addressing symptoms of LET, eccentric-concentric contractions combined with isometrics may be more effective. Human movement professionals may consider these findings when optimizing exercise selection for individuals presenting with LET and forearm dysfunction. |
| Researchers' Conclusions | “The results of this trial indicate that eccentric-concentric training combined with isometric contraction produced the largest treatment effect at the end of treatment and follow-up.” |
Wrist Extension Inhibitation
Review & Commentary:
This study adds to a growing body of research investigating treatment of lateral elbow tendinopathy (LET) by comparing 3 exercise protocols; eccentric-concentric, eccentrics, and eccentric-concentric and isometrics (2-4). This study suggests that the best outcomes were achieved using a combination of eccentric-concentric and isometric contractions.
- This study had many strengths, including:
- To our knowledge, this study is the first to compare 3 commonly used exercise protocols for addressing LET based on pain, strength and perceived function.
- The researchers should be applauded for the use of a randomized control trial design; a challenging and rare methodology in research comparing exercise intervention.
- Individuals were initially assessed, assessed again after 4 weeks of treatment, and then assessed 4 weeks post treatment to determine the carry-over of each protocol.
- Weaknesses that should be noted prior to clinical integration of the findings include:
- The participants were all active tennis players, which may reduce the generalizability of the study to other populations.
- The exercise programs were not progressed throughout the study. Progressing acute variables (sets, reps, load, complexity) may have enhanced the results of treatment, and may also have demonstrated that progressing from one protocol to the next is superior to any one protocol.
- Additional assessments highlighting movement impairment, and/or changes in objective assessments for grip strength, manual muscle testing weakness, and/or range of motion would have added to the clinical relevance of the study.
How This Study is Important:
To our knowledge, this is the first randomized, comparative study of exercise protocols using various combinations of contractions for the treatment of LET. Although research support the use of eccentric training alone (4), this study implies that a mix of contraction types is preferable.
How the Findings Apply to Practice:
The findings demonstrate that adding isometric, concentric and eccentric wrist extension exercise to a rehabilitation program for individuals with LET is more effective in decreasing pain and improving function. That is, a combination of contraction types is more effective than a program designed to emphasize one contraction type. It should be noted that all 3 protocols used in this study were effective, that a progression of exercise protocols was not tested, and there may be benefit to progressing from one contraction type to multiple contraction types over a treatment period.
How does it relate to Brookbush Institute Content?
The Brookbush Institute (BI) uses an integrated approach to addressing postural dysfunction and movement impairment . Although a predictive model of forearm dysfunction has yet to be published, early hypotheses of osteokinematic dysfunction include excessive pronation, ulnar deviation and wrist extension. This study supports the use of exercise, including concentric, eccentric and isometric contractions, for forearm and elbow dysfunction, specially lateral elbow tendinopathy.
The BI addresses over-active muscle groups with self-administered release techniques , lengthening techniques and may reinforce those techniques with inhibition taping and under-active muscles are addressed with activation techniques, followed by function activities. Sample videos of techniques used for the treatment of elbow/forearm/wrist dysfunction below:
Wrist Extensor Self-administered Static Release
Flexor (Wrist) Activation
Flexor Carpi Radialis Activation:
Reverse Tyler Twist - Wrist Flexor Isolated Activation
Wrist Extensor Inhibition Taping
Bibliography:
- Bisset, L.M., Vicenzino, B. (2015). Physiotherapy management of lateral epicondylalgia. Journal of Physiotherapy, 61(4), 174-181.
- Peterson, M., Bulter, S., Eriksson, M., & Svardsudd, K. (2014). A randomized controlled trial of eccentric vs. concentric graded exercise in chronic tennis elbow (lateral elbow tendinopathy). Clinical Rehabilitation, 28(9), 862-872.
- Raman, J., MacDermid, J.C., & Grewal, R. (2012). Effectiveness of different methods of resistance exercises in lateral epicondylosis - a systematic review. Journal of Hand Therapy, 25, 5-26.
- Martinez-Silvestrini, J.A., Newcomer, K.L., Gay, R.E., Schaefer, M.P., Korebein, P., & Arendt, K.W. (2005). Chronic lateral epicondylitis: comparative effectiveness of a home exercise program including stretching alone versus stretching supplemented with eccentric or concentric strengthening. Journal of Hand Therapy, 18, 411-420.
© 2017 Brent Brookbush
Questions, comments, and criticisms are welcomed and encouraged -