Viscoelastic stress relaxation in the hamstrings before and after a 10‐week stretching program

We investigated the viscoelastic stress relaxation response before and after a 10‐week hamstrings static stretch program. Methods : The maximal range of motion (ROM max ) and maximal torque (Torque max ) were assessed before and after a 10‐week stretching program. Six 30‐s static stretches at a predetermined torque were performed, and the relative change in stress relaxation was examined. Results : ROM max and Torque max increased by 53% and 82%, respectively ( P  < 0.001). The relative stress relaxation (RSR) decreased significantly for repetition 1 when comparing the pretest (25%) and posttest (21%) values ( P  = 0.003). A significant decrease was also observed for repetitions 2 and 3 ( P  < 0.014), with no significant difference in repetitions 4–6 ( P  > 0.056). Conclusions : Individuals who participated in a 10‐week hamstrings passive–static stretch program had a reduced RSR response. A higher stretch intensity or longer duration may be necessary to achieve RSRs similar to those reported before the stretch program. Muscle Nerve , 2015 Muscle Nerve 51 :761–764, 2015