Invited Presentations

Heat loss responses in athletes

Professor Narihiko Kondo 1

1 Laboratory for Applied Human Physiology, Graduate School of Human Development and Environment, Kobe University, Kobe, Japan Humans have developed such a remarkable system for endurance exercise in the heat, that we could outrun almost all other mammals, including horses. The key for maintaining exercise in the heat may reside in controlling both core body temperature and systemic blood pressure simultaneously. Thus, thermoregulatory research, especially during exercise in the heat, are critical to understanding human adaptation to tropical conditions. During exercise, heat loss (via sweating and skin blood flow) is regulated by two main factors; thermal (core and skin temperature) and work factors (non-thermal; central command, muscle metabo-/mechano-receptors etc.). In addition, these heat loss responses are improved by exercise training. The magnitude of improvement to these responses is associated with 1) the level of maximal oxygen uptake (VO 2 max), 2) the degree of body temperature elevation, and 3) the degree of activation of heat loss responses during exercise training. There are many types of exercise training for improving sports performance and these various types of training may induce differential adaptations in thermoregulatory responses. For example, sprinters and distance runners exhibit different sweating responses. I will present an integrative control of heat loss responses during exercise and then the effect of different types of exercise training on these responses.