The purpose of this study was to compare the effects of static stretching exercises with vibration on postural stability indices in healthy women. This randomized clinical trial was performed in Zahedan University of Medical Sciences, in 2009. Forty-five healthy female students were selected through convenience sampling. Patients were selected based on following inclusion criteria: Age between 18 and 25, lack of pain in ankle joints, no specific sport activity during study, having no history of sensory and motor disturbances in lower extremities, no history of instances such as neuromuscular diseases, abnormal range of movement and deformity in lower extremities, vertigo, ankle joint injury, surgery, balance disorder and cardiac, neurologic, respiratory and rheumatologic diseases. Patients were excluded if they had pain sensation in ankle joint during study, inability to do pre and post intervention tests, doing effective exercises in order to improving balance and no completion of the treatment.
Participants were randomly assigned to one of three equal groups: static stretching exercises, vibration, and control groups. The first group received 5 seconds duration static stretching exercises for 4 weeks, 5 sessions per week, and each session lasted 20 minutes. The second group received vibration with moderate pressure, high- frequency range, 2500 cycles per minute as the same dosage as the first group. Control group did not receive any intervention. Before and after intervention, overall, anteroposterior, and mediolateral stability indices were measured using Biodex Balance System in different positions.