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A Novel Conceptual Model for Human Heat Tolerance
Thomas E Bernard1, S Tony Wolf2, W Larry Kenney3
1College of Public Health, University of South Florida, Tampa, FL.
Exercise and Sport Sciences Reviews
|January 31, 2024
Summary
Human heat tolerance lacks a clear definition. This study proposes using environmental limits of heat balance, considering metabolic rate and clothing, as a novel metric for quantifying heat tolerance.
Area of Science:
- Environmental physiology
- Human thermoregulation
- Occupational health
Background:
- Human heat tolerance lacks a standardized definition and physiological basis.
- Current understanding relies on relative or comparative terms.
- A precise metric is needed to quantify heat stress resilience.
Purpose of the Study:
- To propose a novel, quantifiable metric for human heat tolerance.
- To define heat tolerance based on environmental limits to heat balance.
- To account for metabolic rate and clothing in heat stress assessment.
Main Methods:
- Defining environmental limits where heat balance becomes uncompensable.
- Integrating metabolic rate and clothing insulation into the calculation.
- Establishing a framework for quantifying heat tolerance based on these limits.
Main Results:
- A novel metric for heat tolerance is proposed, based on environmental limits.
- This metric quantifies heat stress by identifying uncompensable environments.
- It provides a standardized approach accounting for activity and attire.
Conclusions:
- The proposed metric offers a physiological and environmental basis for heat tolerance.
- This approach allows for objective quantification of heat stress risk.
- It has implications for occupational safety and public health in hot climates.
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