The Effect of Static Stretching of the Calf Muscle-Tendon Unit on Active Ankle Dorsiflexion Range of Motion

STUDY DESIGN: Masked randomized trial. OBJECTIVE: To examine the effects of a 6-week program of static stretching of the calf muscle-tendon unit (MTU) on active ankle dorsiflexion range of motion (ADFROM) in healthy subjects. BACKGROUND: Static stretching of the calf MTU is often prescribed to increase flexibility in patients with shortened connective tissues or to maintain ADFROM in healthy individuals. Presently, physical therapists lack specific information on the optimal dosage of calf MTU stretching necessary to produce improvement in ADFROM. METHODS AND MEASURES: One hundred one adults (63 women, 38 men; mean age +/- SD, 40.0 +/- 10.9 years; range, 21-59) with no visual evidence of gait impairment due to lower-extremity dysfunction participated in the study. Active ADFROM was measured with a universal goniometer. Participants were randomly assigned to group 1, no stretch controls (n = 24), or to 1 of 3 experimental groups carrying out a 6-week program of standing wall stretches once per day: individuals in group 2 stretched for 30 seconds (n = 26); individuals in group 3 stretched for 1 minute (n = 24); individuals in group 4 stretched for 2 minutes (n = 27). RESULTS: After 6 weeks, the results of an analysis of variance found no effect of treatment on active ADFROM. CONCLUSION: The results of this study show that a 6-week program of once-per-day static stretching for up to 2 minutes is not sufficient to increase active ADFROM in healthy subjects.