What are the warning signs of heat illness, and what should I do?

Early signs of distress: NFHS (October 2025) says athletes often show early signs of developing heat illness. If you spot them and act promptly by stopping or easing the activity, resting and treating the athlete, serious injury can usually be avoided. The athlete can often return once the signs and symptoms have resolved. Don't delay first aid.

Serious signs (possible exertional heatstroke):

• Clumsiness or stumbling
• Collapse
• Obvious behavior changes or other central nervous system problems

If you see serious signs:

1. Stop the activity immediately.
2. Call 911 (activate EMS).
3. Start rapid cooling on site right away, ideally by immersing the athlete in a tub of cold or ice water, or using a tarp (the "TACO" method).
4. Cool first, transport later. Immediate rapid cooling can prevent death.

Exertional heatstroke is the leading preventable cause of death in high school athletics.