Sports Medicine

, Volume 34, Issue 1, pp 9–16 | Cite as

Heat Illness in Athletes

The Dangerous Combination of Heat, Humidity and Exercise
  • Eric E. Coris
  • Arnold M. Ramirez
  • Daniel J. Van Durme
Leading Article


In 1980, 1700 people died during a prolonged heat wave in a region under-prepared for heat illness prevention. Dramatically underreported, heat-related pathology contributes to significant morbidity as well as occasional mortality in athletic, elderly, paediatric and disabled populations. Among US high school athletes, heat illness is the third leading cause of death.

Significant risk factors for heat illness include dehydration, hot and humid climate, obesity, low physical fitness, lack of acclimatisation, previous history of heat stroke, sleep deprivation, medications (especially diuretics or antidepressants), sweat gland dysfunction, and upper respiratory or gastrointestinal illness. Many of these risk factors can be addressed with education and awareness of patients at risk. Dehydration, with fluid loss occasionally as high as 6–10% of bodyweight, appears to be one of the most common risk factors for heat illness in patients exercising in the heat. Core body temperature has been shown to rise an additional 0.15–0.2°C for every 1% of bodyweight lost to dehydration during exercise.

Identifying athletes at risk, limiting environmental exposure, and monitoring closely for signs and symptoms are all important components of preventing heat illness. However, monitoring hydration status and early intervention may be the most important factors in preventing severe heat illness.


Core Body Temperature Heat Stroke Cold Water Immersion Advanced Cardiac Life Support Heat Illness 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



No sources of funding were used to assist in the preparation of this manuscript. The authors have no conflicts of interest that are directly relevant to the content of this manuscript.


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Copyright information

© Adis Data Information BV 2004

Authors and Affiliations

  • Eric E. Coris
    • 1
  • Arnold M. Ramirez
    • 1
  • Daniel J. Van Durme
    • 1
  1. 1.Department of Family Medicine, Division of Sports MedicineThe University of South Florida College of MedicineTampaUSA

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