The effect of medical grade compression garments on the repeated-bout effect in non-resistance-trained men.

Abstract

What is the central question of this study? What are the effects of compression garments on recovery from unaccustomed damaging exercise and subsequent protective adaptations? What is the main finding and its importance? Compression did not influence recovery, but was associated with blunted protective adaptations for isokinetic performance, which were completely absent at high velocities. Based on these findings, the use of compression garments for recovery would not be recommended following unaccustomed exercise, particularly if the maintenance of high-velocity performance following exercise-induced muscle damage is desirable. Whilst compression garments (CG) may enhance recovery from exercise-induced muscle damage (EIMD), many recovery strategies can attenuate adaptative responses. Therefore, the effects of CG on recovery from EIMD, and the rapid protective adaptations known as the repeated bout effect (RBE) were investigated. Thirty-four non-resistance-trained males (18-45 years) randomly received class II medical-grade CG or placebo for 72h following eccentrically-focused lower-body exercise, in a double-blind, randomised controlled trial. Indices of EIMD were assessed at baseline, 0, 24, 48 and 72h post-exercise, before exercise and testing were repeated after 14days. Results were analysed using a three-way (time × condition × bout) linear mixed-effects model. Exercise impaired isometric and isokinetic strength, with soreness and thigh circumference elevated for 72h (P<0.001). Compression did not enhance recovery (P>0.05), despite small to moderate effect sizes (ES, reported alongside 90% confidence intervals) for isokinetic strength (ES from 0.2 [-0.41, 0.82] to 0.65 [0.03, 1.28]). All variables recovered faster after the repeated bout (P<0.005). However, RBE for peak isokinetic force was impaired in CG at 60°s-1 (group × bout interaction: χ2 =4.24, P=0.0395; ES=-0.56 [-1.18, 0.07]) and completely absent at 120°s-1 (χ2 =16.2, P<0.001, ES=-0.96 [-1.61, -0.32]) and 180°s-1 (χ2 =10.4, P=0.001, ES=-0.72 [-1.35, -0.09]). Compression blunted RBE at higher isokinetic velocities without improving recovery in non-resistance-trained males, potentially contraindicating their use following unaccustomed exercise in this population.