Effects of gastrocnemius stretching on ankle dorsiflexion and time-to heel-off during the stance phase of gait

The purpose was to determine the effects of a gastrocnemius stretching program on passive ankle dorsiflexion range of motion and ankle dorsiflexion and time-to-heel-off during the stance phase of gait. This study was a randomized-control trial design. The study was conducted in a biomechanical laboratory setting. Nineteen volunteers (17 women and 2 men, mean age=30.3 years; SD=9.8 years), with less than 8° of passive ankle dorsiflexion range of motion bilaterally and a history of lower extremity overuse injury were randomly assigned to the experimental ( n=11) or control group ( n=8). The experimental group participated in a static gastrocnemius stretching program of five repetitions held for 30-s, two times daily, for 3 weeks. The control group received no intervention. Passive ankle dorsiflexion range of motion and ankle dorsiflexion and time-to-heel-off during the stance phase of gait were measured before and after the intervention. The experimental group had significantly greater passive dorsiflexion range of motion at post-test than the control group on both the right ( p=0.000) and left ( p=0.002) sides. Ankle dorsiflexion and time-to-heel-off during the stance phase of gait were not different among group, time, or foot ( p>0.05). A gastrocnemius stretch performed two times daily, for 3 weeks increased passive ankle dorsiflexion, but did not alter ankle dorsiflexion or time-to-heel-off during the stance phase of gait. Thus, when an increase in ankle dorsiflexion or time-to-heel-off during the stance phase of ambulation is a clinical goal, it is unlikely to result from the stretching regimen used in this study.