Heat, health, and humidity in Australia's monsoon tropics: a critical review of the problematization of 'heat' in a changing climate

Exposure to heat has killed more people in Australia than all other natural hazards combined. As the climate warms, temperatures are projected to rise substantially, increasing the impact of heat stress and heat illness nation-wide. The relation between heat and health is profoundly complex, however, and is understood differently across multiple sectors. This paper thus provides a critical review of how heat is currently measured and managed in Australia, highlighting how humidity, exposure, and exertion are key elements that are not consistently incorporated into 'problematizations' of heat. The presence or absence of these elements produces different spatial and temporal geographies of danger, as well as different governance practices. In particular, the invisibility of humidity as having a significant impact on heat and health shapes whether Australia's tropical monsoon zone is visible as a region at risk or not, and whether prolonged periods of seasonal heat are treated as dangerous. Similarly, different populations and practices become visible depending on whether the human body (its exposure, exertion, cooling, and hydration) is included in accounts of what constitutes 'heat.' As a result, the outdoor, manual workforce is visible as a population at risk in some accounts but not others. A brief review of key policy areas including housing, public health and work health and safety is presented to demonstrate how specific problematizations of heat are critical to the identification of, and response to, current and future climatic conditions. This has implications for how populations, places, and practices are constituted in the region

Evaluation of pre-game hydration status, heat stress, and fluid balance during professional soccer competition in the heat

This study evaluated initial hydration status (stadium arrival urine specific gravity), fluid balance (pre- and post-game nude body weight, fluid intake, urine collection), and core temperature changes (pre-game, half-time, post-game) during a professional soccer game. We monitored 17 male players (goalies included) between stadium arrival and game end (3h), playing at 34.9°C and 35.4% relative humidity, for an average Wet Bulb Globe Temperature (WBGT) heat stress index of 31.9°C. Data are mean ± SD (range). Initial urine specific gravity (USG) was 1.018 ± 0.008 (1.003-1.036); seven players showed USG ≥ 1.020. Over the three hours, body mass (BM) loss was 2.58 ± 0.88kg (1.08-4.17kg), a dehydration of 3.38 ± 1.11%BM (1.68-5.34%BM). Sweat loss was 4448 ± 1216mL (2950-6224mL), vs. fluid intake of 1948 ± 954mL (655-4288mL). Despite methodological problems with many players, core temperatures greater than or equal to 39.0°C were registered in four players by halftime, and in nine by game’s end. Many of these players incurred significant dehydration during the game, compounded by initial hypohydration; thermoregulation may have been impaired to an extent we were unable to measure accurately. We suggest some new recommendations for soccer players training and competing in the heat to help them avoid substantial dehydration.Gatorade Sports Science Institute//Universidad de Costa Rica VI-245-A4-303UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Centro de Investigación en Ciencias del Movimiento Humano (CIMOHU