Most healthy children and adolescents can safely participate in outdoor sports and other physical activities in a wide range of challenging warm to hot weather,
The presence of one or more of the following factors, however, increases the risk of exertional heat illness:
- Hot and/or humid conditions (remember, however, that exertional heat illness, including heat exhaustion and heat stroke, can occur even if it isn't hot and humid);
- Poor preparation
- Excessive physical exertion
- Insufficient rest/recovery time between repeat bouts of high-intensity exercise (e.g. repeat wind sprints)
- Insufficient access to fluids and opportunities to rehydrate;
- Multiple same-day sessions
- Insufficient rest/recovery time between practices, games, or matches
- Obesity (BMI ≥ 85th percentile for age)(1)
- Chronic illness, including
- Other chronic or acute medical condition or injury that adversely affects water-electrolyte balance, thermoregulation, and exercise-heat tolerance;
- Anticholinergic drugs or certain medications that affect hydration or thermoregulation (e.g. a dopamine-reuptake inhibitor used to treat attention-deficit/hyperactivity disorder or performance enhancing drugs or diuretics);
- Current or recent illness, especially if it involves/involved gastrointestinal distress (e.g. vomiting, diarrhea) and/or fever;
- Clothing, uniforms, or protective equipment that contribute to excessive heat retention (football/lacrosse helmets, football shoulder pads, field hockey/lacrosse goalie equipment);
- Sickle cell trait (exertional sickling).
- Practices lasting longer than 2 hours (1)
- Football (1)
As heat and humidity increase, and as additional exertional heat-illness risks are present, the need to take steps to prevent heat illness becomes more urgent. Likewise, as the number of risk factors for exertional heat illness increases, the maximum environmental heat and humidity level for safe exercise, sports participation, or other physical activities will decrease.
Source: Bergeron MF, Rice SG, DiLaura Devore C & Council on Sports Medicine and Fitness and Council on School Health. Policy Statement - Climactic Heat Stress and Exercising Children and Adolescents. Pediatrics 2011; 128(3) (published on line August 8, 2011).
Updated May 2, 2013
1. Kerr ZY, Casa DJ, Marshall SW,Comstock RD. Epidemiology of Exertional Heat Illness Among U.S. High School Athletes. Am J Prev Med 2013;44(1):8 -14.