Abstract
Cold-water immersion (CWI) has become a widely adopted method for post-exercise recovery. However, its effectiveness in restoring neuromuscular function remains inconclusive. This study examined the impact of CWI on recovery following high-intensity interval exercise (HIIE). Twelve young, recreationally active individuals (10 males, 2 females) participated in a randomized crossover study. Each session included six sets of 30-s all-out isokinetic concentric contractions of the ankle dorsiflexor and plantar flexor muscles, followed by 10 min of room temperature rest (RT) or CWI at 10°C. Neuromuscular function and intramuscular temperature were evaluated periodically over 24 h, as well as next-day fatigue resistance of the dorsiflexors. In both conditions, maximal voluntary contraction torque remained impaired for up to 3 h without significant changes in voluntary activation (p > 0.05). Electrically stimulated torque showed no difference in the fatigue-induced decline or recovery of 10 Hz torque, which also remained impaired for up to 3 h. However, 50 Hz torque recovered within 1 h following RT, whereas it remained slightly reduced for up to 3 h following CWI. The 10:50 Hz torque ratio showed immediate recovery with CWI, whereas RT recovery was delayed for up to 1 h. Notably, the ratio was significantly lower with RT at 0-, 0.5-, and 1-h post-intervention. Despite these differences, HIIE performance during a repeat bout conducted 24 h later remained similar. In conclusion, 10 min of CWI at 10°C does not enhance post-exercise recovery or next-day exercise performance following HIIE.