Résumé
Football (soccer) is played in various environments and, in some parts of the world, domestic and international matches are performed in challenging environmental conditions where the ambient temperature may exceed 30°C with a high relative humidity (>60%). The extra burden of thermal stress that is added to the physical demand associated with match play compromises the footballers' fatigue resistance. Many factors, such * Corresponding Author Email: franck.brocherie@insep.fr. Franck Brocherie, Olivier Girard, Grégoire P. Millet et al. 2 as thermoregulatory, cardiovascular and/or metabolic stress, may contribute to the reductions in match performance capacity (i.e., shorter distance covered in the second vs. first half and toward match-end with decrements in high-intensity running activities in the last 15-min period) and match-related fitness (i.e., post-match jump height and repeated-sprint ability) in the heat. Although heat stroke is unusual in football, the consequences of hyperthermia (i.e., core temperature >39°C) are serious, possibly participating in the development of health issues. Heat acclimatization/acclimation appears as the primary strategy to minimize the thermal stress and the physiological risks of heat-related illnesses when playing football in hot conditions. This can be partly achieved after 6-10 days of training in the heat, with a targeted minimal core temperature of 38.5°C for at least 60 min in each training session, associated to elevated skin temperature and profuse sweating. Another strategy is to ensure that footballers are well hydrated at all times, while enough fluid should be provided before, during, and after matches. Manipulating warm-up and/or implementing cooling interventions (e.g., cold-water immersion, cooling garments) before each match or training or during half-time could be beneficial to optimize physiological readiness for football competition in the heat. Hence, the aims of this chapter are to present (i) the football match-and training-induced responses when performed in hot and/or humid conditions and (ii) the strategies employed to better cope with such challenging environments.