Intense exercise causes damage to your muscle fibers. But you might not feel sore until a day or so later. This is called delayed onset muscle soreness (DOMS). Researchers measured both DOMS and muscle weakness in elite athletes following strenuous workouts found that contrast bath therapy improved both the soreness and weakness better than passive resting alone (5). Less damage leads to less inflammation, which in turn reduces soreness and helps restore physical performance the next day (6). Recover hard, train harder!