Foam Rolling Effect on Hamstring Flexibility in Crossfit Athletes

Background/Purpose: High-density foam rolling has become an increasingly popular method of attempting self-myofascial release for athletes and recreationally active individuals who believe foam rolling (FR) will increase the flexibility of muscles, improve performance and reduce injuries.  Myofascial release requires pressure to be put on a tight fascial trigger point which then causes the tissue to loosen (Barnes, 1997).  A foam roller, a firm cylindrical tube that is made in a variety of diameters, is commonly used to apply that pressure to a muscle group as the user rolls a body part over the tube.   The limited research that has investigated FR suggests that this practice is highly beneficial.  The purpose of this study was to determine the effect of FR on hamstring flexibility of male Crossfit participants.  It was hypothesized that FR the hamstring for thirty seconds would increase the flexibility of the hamstring muscles. 

Method: Twenty male Crossfit athletes (n = 20, ht. = 182.11 ±  5.52 cm.; wt = 89.62 ± 11.71 kg,; age = 37.7 ± 9.01) performed a Crossfit workout consisting of deadlifts, pushups, pull-ups, and lunges prior to the hamstring flexibility measurement.  The supine straight leg flexion test was administered to the right (RH) and left (LH) hamstrings.   Range of motion was measured at the hip joint in degrees with a Saunders inclinometer.  Participants FR each hamstring for 30 seconds prior to a second hamstring flexibility measurement.  Data was analyzed using a two-tailed paired t-test in Minitab 16 at the p < 0.05 level. 

Analysis/Results: RH flexibility pre-FR (91.05 ± 19.55) was statistically different (p = 0.007) from post-FR (94.85 ± 20.39) flexibility.  LH flexibility pre-FR (92.60 ± 17.04) was also statistically different (p = 0.0013) from flexibility post-FR (95.95 ± 18.89).

Conclusions: Based on the statistical analysis, FR is an effective method of self-myofascial release that results in improved hamstring flexibility.  Athletes who want to increase hamstring flexibility may find FR an easy way to perform self-myofascial release which results in improved hamstring flexibility.  Coaches and athletic trainers may find it beneficial to recommend to athletes with tight hamstrings that they use a foam roller to improve hamstring flexibility.