During heat stress, the human body relies on conduction, convection, and radiation but predominantly on sweating and evaporation to maintain thermal homeostasis. Problems can arise in a state of uncompensable heat stress. Uncompensable heat stress is when the heat loss required from sweating exceeds the evaporative capacity of the immediate ambient environment, resulting in continuous heat storage. 

Core temperature assessment can prevent heat-related illness, mortality, and specific physiological and cognitive complications. The literature specifies that specific core temperature points are markers of objective measures of adverse outcomes. Research demonstrates that cognitive issues are associated with increased core temperature. A rapid core temperature acquisition up to 39.5°C is related to cognitive decline, subsequently impacting one’s decision-making ability. Also, a rapid rise in core temperature to > 40°C is linked to heat stroke and central nervous system dysfunction. Despite the apparent consequences of elevated core temperature, employers, coaches, and other supervisory personnel rely on subjective assessments such as visual cues to identify detrimental heat-related issues. These techniques can delay the identification of the problem and subsequent treatment. Therefore, valid, reliable, and deployable direct and predictive methods are necessary to evaluate core temperature in the athletic and occupational environment.

Current methods include but are not limited to 1) Wearable sensors 2) Subcutaneous Temperature Measurement 3) Infrared Thermography 4) Telemetry systems 5) surgical implantation of temperature sensors and 6) Algorithms. This collection aims to bring current methods to light and highlight innovative future methods being developed.