Duration of stretching effect on range of motion in lower extremities.

The duration of the effect of contract-relax stretching on range of motion (ROM) in the lower extremities was measured on eight male volunteers. The stretching procedure was performed as one isometric contraction, followed by relaxation and then a passive extension of the muscle being stretched. The treated muscle groups were the adductors, hamstrings, rectus femoris, iliopsoas, gastrocnemius, and soleus. The total stretching time was 15min. Six ROMs were tested 0, 30, 60, and 90min after the stretching procedure. There was a significant increase in hip abduction (+17% +/- 3), knee flexion (+4% +/- 1), hip flexion (+4% +/- 2), ankle dorsiflexion with knee flexed (+18% +/- 7), and ankle dorsiflexion with knee straight (+16% +/- 5). The increase remained for 90min for all ROMs except for ankle dorsiflexion with the knee straight.