Foam Rollers Show No Increase in the Flexibility of the Hamstring Muscle Group

OBJECTIVE: Recent claims suggest foam rollers are useful in self-myofascial release and are a stretching technique used by health care professionals to treat patients with a variety of soft tissue conditions including muscle tightness. The purpose of this study was to determine if foam rollers are beneficial in gaining range of motion (ROM) in the hamstring muscle group. DESIGN AND SETTING: All subjects’ ROM was tested prior to the beginning of the stretching protocol. All stretching routines were performed three times a week in the Mitchell Hall athletic training room. Treatment consisted of three-one minute stretching bouts with a one minute rest between each stretch. The control group was instructed to continue with normal activity, but to perform no additional stretching. SUBJECTS: Twenty-three male and female college students (ages 18-32) from the University of WisconsinLa Crosse participated in this study. All subjects were healthy with no history of recent injury. The criterion for subject inclusion was tight hamstrings as defined by a knee extension range of motion less than 80 ̊. MEASUREMENTS: Active knee extension measurements were determined using an inclinometer and a Flexometer® before the start of the stretching program, at four weeks and at the conclusion of eight weeks. RESULTS: A doubly multivariate repeated measures analysis was used to interpret the data. The statistical significance was set at p<0.05. The analysis showed no significant difference (p<0.05) between the treatment and control groups. CONCLUSIONS: No increased range of motion was associated with the use of the foam rollers after the eight week study. Therefore, our findings suggest stretching the hamstrings using foam rollers may not be an effective technique for increasing range of motion in this muscle group.