Exertional Heat Illness in American Football Players: When Is the Risk Greatest?

Area of Science:

• Sports Medicine
• Environmental Health
• Epidemiology

Background:

• Limited knowledge exists on environmental and practice risks during American intercollegiate football preseason.
• Identifying these risks is crucial for mitigating exertional heat illness (EHI) occurrences.

Purpose of the Study:

• To evaluate associations between preseason practice day, session number, and wet bulb globe temperature (WBGT) and EHI incidence.
• To inform preventive strategies for athlete safety during football preseason.

Main Methods:

• A descriptive epidemiology study was conducted across 60 US colleges and universities.
• Data on practice day, session number, and WBGT (measured every 15 minutes) were collected for NCAA football players.
• EHI incidence and athlete-exposures (AEs) were recorded and analyzed.

Main Results:

• An overall EHI rate of 1.52 per 1000 AEs was reported (553 cases).
• Exertional heat cramps accounted for 74% of EHIs; heat syncope and exhaustion comprised 26%.
• Highest EHI rates occurred within the first 14 days of preseason, particularly the first 7 days. EHI risk significantly increased at WBGT ≥ 82.0°F (27.8°C).

Conclusions:

• EHI rates are elevated during the initial 14 days of preseason practice, with the highest risk in the first 7 days.
• Elevated WBGT (≥ 82.0°F) is associated with a substantial increase in EHI rates.
• Sports medicine professionals must implement preventive measures during the early preseason and in high heat conditions (WBGT > 82.0°F).