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Updated: Mar 30, 2026

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Self-Myofascial Release: No Improvement of Functional Outcomes in 'Tight' Hamstrings
Robert W Morton1, Sara Y Oikawa, Stuart M Phillips
1Dept of Kinesiology, McMaster University, Hamilton, ON, Canada.
Purpose:
Self-myofascial release (SMR) is a common exercise and therapeutic modality shown to induce acute improvements in joint range of motion (ROM) and recovery; however, no long-term studies have been conducted. Static stretching (SS) is the most common method used to increase joint ROM and decrease muscle stiffness. It was hypothesized that SMR paired with SS (SMR+SS) compared with SS alone over a 4-wk intervention would yield greater improvement in knee-extension ROM and hamstring stiffness.
Methods:
19 men (22 ± 3 y) with bilateral reduced hamstring ROM had each of their legs randomly assigned to either an SMR+SS or an SS-only group. The intervention consisted of 4 repetitions of SS each for 45 s or the identical amount of SS preceded by 4 repetitions of SMR each for 60 s and was performed on the respective leg twice daily for 4 wk. Passive ROM, hamstring stiffness, rate of torque development (RTD), and maximum voluntary contraction (MVC) were assessed pre- and postintervention.
Results:
Passive ROM (P < .001), RTD, and MVC (P < .05) all increased after the intervention. Hamstring stiffness toward end-ROM was reduced postintervention (P = .02). There were no differences between the intervention groups for any variable.
Conclusion:
The addition of SMR to SS did not enhance the efficacy of SS alone. SS increases joint ROM through a combination of decreased muscle stiffness and increased stretch tolerance.
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