Author and graduation date: Wendy E. HILL, May, 1997

Committee members: Peter M. Aufesser (Chair), Robert J. Moore, Denise L. Wiksten, William E. Piland

Thesis title: Comparison of Static Versus PNF and Its Effect on Hamstring and Hip Flexor Flexibility in Division I College Football Players

The purpose of this study was to compare two stretching techniques static versus static and PNF and measure its effects on flexibility of the hamstring and hip flexor muscles in Division I college football players over a 6-week time period. Twenty-eight males representing a football team from a Division I college in Southern California whose ages ranged from 18-23 years old agreed to participate in this study. Fourteen players which consisted of two players randomly drawn from each of the following positions; defensive backs, running backs, wide receivers, tight ends, linebackers, and defensive and offensive linemen participated in the experimental group. Fourteen additional players, selected the same way, participated in the control group. The subjects were tested for range of motion using a goniometer in the hamstring and hip flexor muscles prior to and after the 6-week stretching program. The sit and reach field test was also used pre and post the 6-week stretching program to examine hamstring flexibility. Both the control and the experimental group participated in a controlled static stretching routine. The experimental group participated in additional PNF hold-relax stretches, and the control group performed additional static stretches. All 28 subjects completed the study and performed the necessary physical training such as the weight lifting, speed, and agility training without any injury or muscle strain.

A two-way repeated measures analysis of variance revealed a significant time effect, F(1, 27) = 280.2; p <.05, and a significant interaction, F(1, 27) = 26.5 1; p <.05, demonstrated by both the control and the experimental groups in the first hamstring test. A significant time effect, F(1, 27) = 319.08; p <.05, and a significant interaction, F(1, 27) = 50.03; p <.05, was demonstrated by both the control and the experimental groups for the second hamstring test. A significant time effect, F(1, 27) = 271.25; p <.05, and a significant interaction, F(1, 27) = 47.17; p <.05, was demonstrated by the control and the experimental groups for the hip flexor test. A significant time effect, F(1, 27) = 55.5 1; p <.05, and a significant interaction, F(1, 27) = 9.64; p <.05) was demonstrated by both the control and the experimental groups for the sit and reach test scores. It is recommended that future research should focus on the long term effect of the PNF hold-relax technique used either separately or combined with static stretching and measure its effect on range of motion and injury prevention in Division I college football players.

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