Heat Therapy to Accelerate Muscle Recovery

The use of cold on muscle (Ice, Cold Water Immersion - CWI or cryotherapy) is a widespread practice used by health professionals, athletes or non-athletic population in the treatment of muscle soreness and soft tissue injuries. Application of cold on muscle is well known to decrease inflammation and reduce pain perception. However, some studies in humans and animals have reported contrasted effects of cold on muscle regeneration. On the other hand, recent studies in humans suggest that passive heat exposure can impact positively muscle protein synthesis, mitochondrial content and muscle torque in different types of populations. Rodent studies comparing heat and cold modalities following a muscle injury have reported that only repeated heat exposure enhances cross sectional area, accelerate macrophage infiltration in damaged fibers and enhances satellite cells activation which led to a faster muscle regeneration. As such heat therapy may be a promising tool to accelerate recovery after muscle injury. This study will investigate the effect of three distinct thermal interventions (Hot, Cold and Thermoneutral water immersion) on human skeletal muscle regeneration after an eccentric exercise. 36 participants will be distributed in a counterbalanced way into 3 groups being immersed for 15min to 1h per day in either HEAT or COLD or NEUTRAL water for 10 days following eccentric contractions.