OBJECTIVE: The practice of physical exercises leads to dehydration due to heat production. Most studies that address the risks of dehydration and provide recommendations for restoring water are directed to adults living in temperate climate regions, but little is known about the needs of restoring water to physically active children in tropical regions. This review discusses the recommendations for this population and the risks of sports practice in tropical climate areas. DATA SOURCE: Systematic analysis of the national (SciELO) and international (Medline) literature from 1972 to 2009, with the following keywords, alone or in combination, in Portuguese and English: hydration, children, dehydration and water replacement. DATA SYNTHESIS: There are risks related to dehydration and possible development of hyperthermia especially in adverse weather conditions without adequate fluid replacement. The main trigger for hyperthermia is that, compared to adults, children are less able of adapting to extremes of temperature due to their higher body surface area and lower capacity of thermoregulation by evaporation. Studies on this subject are scarce in face of the questions still open. CONCLUSIONS: Once dehydration factors are known, the best recommendation to aggressive climatic conditions is to establish a replacement program using flavored hydration beverage added with carbohydrates and sodium in order to avoid significant water losses and reduced performance, and to decrease health risks posed by hyperthermia and dehydration to physically active children.
dehydration; heat exhaustion; sweating; physical exertion
