Environmental Condition and Monitoring
The ambient environment (i.e., weather conditions) can significantly impact one’s ability to thermoregulate, particularly when exercising in environmentally stressful conditions where an imbalance between metabolic heat production and heat dissipation from the body is not adequately regulated. Empirical, direct, and rational heat indices have been developed by scientists to gauge the degree of heat strain one may experience in a range of thermal conditions. These measures are applied in athletic, military, and occupational settings to provide guidance on physical activity and/or clothing modifications that mitigate the risk of experiencing exertional heat illness. This chapter will provide an overview of common heat indices in physical activity settings and highlight the benefits and drawbacks of each index in practical applications. Lastly, the chapter will provide a case example from the Georgia High School Association in developing a set of weather-based activity modification guidelines based on an empirical study of football players’ heat injuries.
KeywordsHeat balance Wet bulb globe temperature Heat index Humidex Environmental stress index Heat stress index Physiological strain index Thermal work limit Universal thermal comfort index Activity modification
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