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J Athl Train. 1999 Jul-Sep; 34(3): 246–252.
PMCID: PMC1322918

Exercise in the Heat. I. Fundamentals of Thermal Physiology, Performance Implications, and Dehydration

Douglas J. Casa, PhD, ATC, CSCS



To present the critical issue of exercise in the heat in a format that provides physiologic foundations (Part I) and then applies the established literature to substantial, usable guidelines that athletic trainers can implement on a daily basis when working with athletes who exercise in the heat (Part II).

Data Sources:

The databases MEDLINE and SPORT Discus were searched from 1980 to 1999, with the terms “hydration,” “heat,” “dehydration,” “cardiovascular,” “thermoregulatory,” “physiology,” and “exercise,” among others. The remaining citations are knowledge base.

Data Synthesis:

Part I introduces athletic trainers to some of the basic physiologic and performance responses to exercise in the heat.


The medical supervision of athletes who exercise in hot environments requires an in-depth understanding of basic physiologic responses and performance considerations. Part I of this article aims to lay the scientific foundation for efficient implementation of the guidelines for monitoring athletic performance in the heat provided in Part II.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.3M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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Articles from Journal of Athletic Training are provided here courtesy of National Athletic Trainers Association