Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

Heat exposure represents a challenge to the human body. However, the human body has the ability to adapt when it is repeatedly exposed to the heat. This process, termed heat acclimation, allows the body to better control its internal temperature. Extensive research has described the signs of heat acclimation in humans, yet the physiological changes which accompany these signs remain poorly understood. The goal of this research program is to determine and better understand the physiological changes that accompany heat acclimation in humans. To achieve this goal, studies will be performed to address 5 objectives. The first objective is to identify the method of heat acclimation that provides optimal adaptations. The second objective is to examine the relative contribution of central (nervous system) and peripheral (sweat glands, skin blood vessels) changes that lead to a better control of internal body temperature. The third objective is to examine blood volume and heat shock proteins as potential physiological mechanisms which lead to heat acclimation. The fourth objective is to examine adaptations following heat acclimation in systems that are not directly related to the control of internal body temperature. Specifically, changes within the cardiovascular and autonomic systems will be studied. The fifth objective will determine how age affects the ability of the body to acclimate to the heat. The results from this research program will further our understanding regarding the ability of the human body to adapt to heat exposure. This knowledge could lead to better strategies aimed at improving the work of Canadians in industrial and/or military settings who must perform their duties despite hot environmental conditions. Such strategies are particularly needed, as Canadian workers are already enduring above-average ambient temperatures and they are expected to be exposed to a greater frequency, intensity and duration of extreme heat events in the near future.