RR-PL-0832

Tuesday 10:20, Palau de Congressos, Hall 5, Room 7

THE ACUTE EFFECT OF PLYOMETRIC EXERCISE ON ISOMETRIC PEAK TORQUE OF THE QUADRICEPS MUSCLES. Kajimoto H, Yamaguchi H, Goto M; Department of Physical Therapy. Aino Hospital. Ibaraki. Japan. PURPOSE: Plyometric exercise is used to heighten the excitability of the nervous system for improved reactive ability of the neuromuscular system. The purpose of this study are 1) to determine the effect of plyometric exercise on isometric peak torque of the quadriceps femoris muscles, and 2) to compare the effect of double leg tuck jump and in-depth jump on isometric peak torque of the quadriceps femoris muscles. SUBJECTS: Eighteen healthy volunteer students (7 male and 11 female) from the Aino School of Health and Welfware Sciences were recruited to participate in this study. METHODS: Each subject participated in isometric peak torque measurements of quadriceps femoris muscles under three conditions, without plyometric exercise, after double leg tuck jump, and after in-depth jump. Isometric peak torque was measured using Myoret RZ450 dynamometer (Kawasaki Heavy Industries, Ltd.) ANALYSES: Isometric peak torque without plyometric exercise and after 2 kinds of plyometric exercise were compared using a one-way repeated-measures analysis of variance. RESULTS: The results of the one-way repeated-measures ANOVA showed that plyometric exercise and their order of presentation had no significant effect on isometric peak torque of the quadriceps femoris muscles. CONCLUSION: Practically, plyometric exercise will take advantage of the length-shortening cycle to increase muscular power. The reason why muscular power didn’t increase after plyometric exercise in this study may result from lack of contraction speed on plyometric exercise that subjects performed.