EFFECTS OF ECCENTRIC CONTRACTION INDUCED MUSCLE DAMAGE ON STRETCHSHORTENING CYCLE FUNCTION

  • A. Harrison
  • S. Gaffney
  • A. Donnelly
Keywords: stretch shortening cycle, muscle damage, eccentric contraction, jump

Abstract

This experiment examined the effect of eccentric contraction induced muscle damage on the stretch shortening cycle (SSC). Ten moderately active adult volunteers participated in this study. Temporary muscle damage on the knee extensors was administered by a bout of eccentric contractions on an isokinetic dynamometer. Measurements were obtained of maximum voluntary force, and take off velocities for single leg countermovement jumps (CMJ), squat jumps (SJ) and drop jumps (DJ) performed on a specially constructed sledge and force plate apparatus. Measurements were obtained before and after the damage intervention. The undamaged leg was used as a control. The results indicated that eccentric muscle damage significantly affected SSC performance by causing relatively greater reductions in SJ performance than CMJ or DJ.