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Updated: May 13, 2026
08:22
A Preclinical Model of Exertional Heat Stroke in Mice
Published on: July 1, 2021
Specific exercise heat stress protocol for a triathlete's return from exertional heat stroke
Evan C Johnson1, Fred W Kolkhorst, Allen Richburg
1Department of Kinesiology, University of Connecticut, Storrs, CT 06269, USA. Evan.johnson@uconn.edu
Current Sports Medicine Reports
|March 13, 2013
Summary
Elite triathletes can safely return to competition after exertional heatstroke (EHS) with a tailored heat tolerance test (HTT) and acclimation program. This approach ensures athletes are heat-acclimated and ready for high-intensity racing.
Area of Science:
- Sports Medicine
- Environmental Physiology
- Exercise Science
Background:
- Exertional heatstroke (EHS) poses a significant risk for triathletes, necessitating careful return-to-play protocols.
- Traditional heat tolerance tests (HTT) may not adequately assess elite athletes' heat tolerance or acclimation capacity.
- Determining an elite triathlete's ability to compete after EHS requires evaluating their heat intolerance and acclimation potential.
Observation:
- A triathlete who experienced EHS underwent a modified HTT involving cycling at 70% V˙O2max in hot conditions (36°C, 50% RH).
- The protocol included 9 days of exercise heat acclimation followed by a repeat heat stress test.
- Key physiological markers monitored included gastrointestinal temperature (Tgi), exercise duration, and sweat rate.
Findings:
- Following heat acclimation, exercise duration before reaching a Tgi of 39.5°C increased by 25 minutes.
- Sweat rate increased by 0.5 L·h, initial Tgi decreased by 0.85°C, and the rate of Tgi rise decreased by 0.6°C·h.
- These physiological adaptations indicated improved heat tolerance and acclimation.
Implications:
- The modified HTT and acclimation strategy allowed the triathlete to safely return to competition.
- This approach provides a viable method for assessing heat tolerance in elite athletes post-EHS.
- It highlights the importance of individualized protocols for managing heat illness risk in sports.
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Definition
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Purposes
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Definition
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Purposes
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