Exercise Under Heat Stress: A Review of Fatigue Mechanisms and Heat Acclimation Strategies for Performance Optimization

Global climate warming has made hot environments an increasingly important factor affecting athletes' health, safety, and athletic performance. Focusing on the mechanisms underlying exercise-induced fatigue and strategies for maintaining exercise performance in hot environments, this review summarizes the interaction between peripheral and central fatigue, the influence of heat-related factors on exercise performance, and the application of heat acclimation and other intervention strategies, while highlighting future research directions. Current evidence indicates that impaired exercise performance in hot environments results from the combined effects of peripheral and central fatigue rather than either mechanism alone. As core temperature increases, descending central motor drive is progressively inhibited, which not only contributes to performance limitation but also serves as a protective mechanism for maintaining physiological homeostasis. Environmental temperature, humidity, and exercise protocols jointly determine heat load accumulation and are therefore important factors influencing heat stress and exercise performance. Heat acclimation enhances heat tolerance through adaptations in hemodynamics, cardiovascular function, and thermoregulatory capacity, whereas nutritional strategies, cooling interventions, and psychological regulation may serve as complementary approaches to help maintain exercise performance in hot environments. Future research should further clarify the physiological and cognitive mechanisms underlying exercise-induced fatigue during heat stress, investigate individual differences in heat adaptation, and promote the integration and practical application of multiple intervention strategies to provide stronger theoretical and practical support for training and competition in hot environments.