Description:
<jats:p>Cold water immersion is often used to recover from exercise in the belief that it reduces muscle soreness and inflammation. However, no data currently exist to support this notion—at least in humans. We compared the effects of cold water immersion versus active recovery on neutrophil and macrophages, pro‐inflammatory cytokines, neurotrophic and growth factors, heat shock proteins and transcription factors in muscle after resistance exercise. In a randomized cross‐over design, 10 active men performed resistance exercise using one leg on separate days. On one day, they immersed their lower body in cold water (10°C) for 10 min after exercise. On the other day they cycled at a low‐intensity for 10 min after exercise. Muscle biopsies were collected from each leg before, 2, 24 and 48 h after exercise. Exercise induced a strong inflammatory response, as indicated by increases in neutrophil and macrophage counts and IL‐1β, TNF‐α, IL‐6 and MCP‐1 mRNA (P<0.05). Growth arrest and DNA damage‐inducible 45 protein (Gadd 45) mRNA also increased markedly (P<0.05). As evidence of hyperalgesia, nerve growth factor (NGF) and glial cell‐line derived neurotrophic factor (GDNF) mRNA increased after exercise (P<0.05). The protein abundance of Forkhead box class O (FOXO) and αB‐crystallin in the cytosolic fraction of muscle homogenates decreased after exercise (P<0.05), indicating nuclear translocation. Despite these robust responses, there were no significant differences in any of these factors between the two trials. Therefore, contrary to popular belief, cold water immersion did not attenuate inflammation or markers of soreness in muscle after intense resistance exercise.</jats:p>