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.

J Orthop Sports Phys Ther. 2003;33(7):408-417.

Key Words: flexibility, lower extremity, rehabilitation, triceps surae

Study Design: Cross-sectional descriptive study. Objectives: To examine the factors of gender and age, stratified by 10-year increments, on hamstring muscle length (HML) as measured by passive straight leg raise (PSLR) and popliteal angle (PA). Background: Differences in HML between men and women have not been examined for a large group of healthy adults over a wide range of ages. The usefulness of these data is to provide some typical values of HML for future reference. Methods and Measures: Two hundred fourteen adults (108 women, 106 men; age range, 20-79 years) with no known history of hip or knee joint disease and no history of recent hamstring strain participated in the study. PSLR (trunk-thigh angle) and PA (thigh-leg angle) were estimated with a goniometer. A 2-way analysis of variance (ANOVA) was used to analyze the effects of 2 independent variables (gender and age) on 2 dependent variables (PSLR and PA). Statistical significance was established at a<.05. Results: HML differed significantly (P<.001) between genders for both methods of measurement, with females demonstrating greater flexibility than their male counterparts. The difference between genders was 8° for PSLR and 11° for PA. HML was not influenced by age. Conclusions: This study provides physical therapists with typical values of HML in healthy men and women.

J Orthop Sports Phys Ther. 2005;35(4):246-252. doi:10.2519/jospt.2005.1428

Key Words: flexibility, hip extensors, lower extremity, straight-leg raise