Comparison of 90-90 passive hamstring stretching technique plus knee to chest position with 90-90 passive hamstring stretching alone in normal healthy individuals of age 18 to 25 years

Hamstring flexibility plays an important role in physical fitness. Hamstring tightness is determined by knee extension deficit. Passive stretching is simple and found effective to improve muscle flexibility. In clinical settings, 90-90 passive stretching test is used whereas knee to chest position stretches proximal ends of hamstrings which leads to isolated hip flexion and causes all three muscles tendons of hamstrings to lengthen to a greater degree because lever arms are larger at the hip. The present study hypothesized that stretching both proximal and distal ends of hamstrings will be more effective than stretching distal end in full range alone. Therefore present study determines whether adding component like knee to chest position to 90-90 passive hamstring stretch enhances the flexibility. Total 200 young healthy individuals (100 Males, 100 Females) of age 18 to 25 years participated in study. Individuals with bilateral hamstring tightness (>20 degrees) were included. Randomly, on one side passive 90-90 stretching technique was applied (60 seconds)and on other side 90-90 passive hamstring technique (30 seconds) plus knee to chest passive stretch (30 seconds) was applied and compared between both genders. Active knee extension test was used as an outcome measure for calculating hamstring tightness angle. Stastically unpaired t- test was used for comparison between tests. Results showed highly significant increase (p=0.0005) in knee extension range of motion with 90-90 passive hamstring stretch plus knee to chest position than 90-90 hamstring stretch alone. Hence, 90-90 passive hamstring stretching technique plus knee to chest position found more effective in hamstring flexibility than 90-90 passive hamstring stretch alone.