The Comparison of Mechanical Percussion Therapy and Manual Stretching on Hamstring Length.

Background: The interest in and use of mechanical percussive massage treatment devices have grown immensely among clinicians and athletes. One purported benefit of these devices is the improvement of range of motion but whether these devices are more effective than traditional means of increasing muscle extensibility remains unexplored. Purpose: To examine the effect of mechanical percussive massage therapy applied to the hamstrings versus static stretching of the hamstrings on passive knee extension (PKE) range of motion. Study Design: Randomized control trial. Methods: Male Division II NAIA and Division III NCAA football players were recruited. Subjects were randomly assigned to one of three groups: control, mechanical percussive massage therapy, or static stretching. Passive hamstring extensibility was quantified in all groups using standard goniometric measurements before and after the intervention by measuring PKE three times in a 90-90 supine position. The mechanical percussive massage therapy group received five minutes of treatment to the hamstrings. The static stretching group received manual stretching of the hamstrings performed in the 90-90 supine position (3 repetitions of 30 seconds with 10-second rest between repetitions). The control group received no treatment. An ANOVA was used to investigate effects of the random interventions. Results: Seventy-nine male collegiate football players, 37 NCAA Division III and 42 NAIA Division II (mean age 19.8 years +/- 1.2) participated in this study. A significant difference (p < .001) in pre- and post-PKE range of motion was noted for both the percussive mechanical massage therapy (5.8 degrees, SD+/- 3.32) and static stretching (6 degrees, SD+/- 3.29) groups. No significant difference was noted between the two treatment groups. The control group did not demonstrate a significant difference in pre and post-PKE (1.1 degrees, SD +/- 3.62). Conclusions: Static stretching and mechanical percussive massage therapy applied to the hamstrings produce significant immediate increases in PKE compared to a control group suggesting that static hamstring stretching, and mechanical percussive massage therapy are both viable options for acutely increasing hamstring extensibility. Level of Evidence: II.