Effect of Preload and Range of Motion on Isokinetic Torque in Women

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
David H. Perrin, Former Provost and Executive Vice Chancellor (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/

Abstract: The purposes of this study were to compare the effects of two preload settings (0 N, 75 N) and two ranges of motion (5-90° ROM, 25-70° ROM) on torque output of the knee musculature. Twenty females were randomly assessed for isokinetic concentric (CON) and eccentric (ECC) torque of the knee extensor (EXT) and flexor (FLEX) musculature at a velocity of 1.62 rads • s-1. Two four-way ANOVAs (muscle x mode x range of motion x preload) revealed significant differences in average torque between the preload and range of motion conditions (CONEXT: 5-90° ROM, 75 N = 74.3 ± 17.2 Nm; 5-90° ROM, 0 N = 68.3 ± 17.2 Nm; 25-70° ROM, 75 N = 79.0 ± 13.0 Nm; 25-70° ROM, 0 N = 71.5 ± 20.8 Nm) (ECCEXT: 5-90° ROM, 75 N = 85.6 ± 28.6 Nm; 5-90° ROM, 0 N = 82.8 ± 27.8 Nm; 2570° ROM, 75 N = 97.7 ± 23.4 Nm; 25-70° ROM, 0 N = 93.6 ± 26.5 Nm) (CONFLEX: 5-90° ROM, 75 N = 43.5 ± 9.2 Nm; 5-90° ROM, 0 N = 43.1 ± 5.6 Nm; 25-70° ROM, 75 N = 44.2 ± 8.9 Nm; 25-70° ROM, 0 N = 41.2 ± 8.9 Nm) (ECCFLEX: 5-90° ROM, 75 N = 56.7 ± 16.3 Nm; 5-90° ROM, 0 N = 55.6 ± 17.8 Nm; 25-70° ROM, 75 N = 57.3 ± 14.0 Nm; 25-70° ROM, 0 N = 51.8 ± 14.0 Nm) (P < 0.05). No differences in peak torque values were observed. Based on the findings of this study, preload and range of motion should remain constant between and among subjects if average torque is used as a criterion measure.

Additional Information

Publication
Medicine and Science in Sports and Exercise, 25, 1038-1043
Language: English
Date: 1993
Keywords
preload, knee extensor, knee flexor, isokinetic, concentric torque, eccentric torque

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