Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Physical Education

First Advisor

Dr. Jack Ewing


The purpose of this investigation was to determine if increasing hamstring flexibility elicited a significant increase in peak quadriceps torque in college-age females. Fifteen college-age females, mean age 18.93 ± 0.77 years, volunteered as subjects for the study. Each subject was pretested and posttested for hamstring flexibility and peak quadriceps torque (Orthotron II set at 60 degrees per second). All subjects completed an eight week treatment program consisting of 10 repetitions of proprioceptive neuromuscular facilitation stretching for the right hamstring muscles, done three times per week, with the left leg used as a control leg. Hamstring flexibility was measured utilizing a Leighton Flexometer, an aluminum hinged device strapped to the lateral side of the leg, and passive straight leg raising. The mean change in flexibility from pretest to posttest on the right leg was +8.71 + 2. 73 degrees and +0.21 ± 1.33 degrees on the left leg. The mean peak torque on the right leg increased 10.31 + 15.91 foot pounds from pretest to posttest while the left leg increased 0.55 + 14.56 degrees. The mean change in the angle at which the peak quadriceps torque occurred from pretest to posttest was -1.51 + 5.12 degrees for the right leg and -0.13 + 4.10-degrees on the left leg. Using paired t-tests a significant difference (p < 0.05) was found in hamstring flexibility between the right and left legs from pretest to posttest. No significant differences were seen in peak quadriceps torque or the angle at which peak torque occurred from pretest to posttest between the right and left legs. Increasing hamstring flexibility does not seem to significantly affect peak quadriceps torque or the angle at which peak torque occurs.

Library of Congress Subject Headings

Muscle strength

Stretch reflex


South Dakota State University Theses



Number of Pages



South Dakota State University