Stretching exercises are commonly prescribed for patients and healthy individuals with limited extensibility of the gastrocnemius muscle.
To determine effects of gastrocnemius stretching on ankle dorsiflexion, knee extension, and gastrocnemius muscle activity during gait.
Sixteen volunteers (9 men and 7 women, mean age = 27 y) with less than 5° of passive ankle-dorsiflexion range of motion randomly assigned to an experimental or control group.
The experimental group performed gastrocnemius stretching for 3 wk.
Main Outcome Measures:
Maximum ankle dorsiflexion, maximum knee extension, and EMG amplitude of the gastrocnemius muscles were measured between heel strike and heel-off before and after intervention.
No significant effect of group or time was found on maximum ankle dorsiflexion, maximum knee extension, or EMG activity of the medial or lateral gastrocnemius muscles between heel strike and heel-off. The experimental group had significantly greater passive ankle-dorsiflexion range of motion bilaterally at posttest than the control group.
Stretching did not alter joint angles or gastrocnemius muscle activity in the early to midstance phase of gait.
Johanson, Cuda, Koontz, and Stell are with the Dept of Rehabilitation Medicine, and Abelew, the Dept of Cell Biology, Emory University School of Medicine, Atlanta, GA.