Knowing the symptoms of EHI and paying attention to your body are important if you want to exercise safely in the heat.
It’s easy to brush off a headache during a pickup basketball game, or attribute weakness and fatigue during a run to something like not getting enough sleep the night before, but your situation may be more serious than that.
Headache, dizziness, nausea, fatigue, and lightheadedness are all telltale signs of heat exhaustion, according to Douglas Casa, Ph.D., professor of kinesiology at the University of Connecticut.
Becoming disoriented or blacking out are both signs of heatstroke, which is a much more serious—even fatal—condition that requires immediate medical attention.
If you find yourself possibly suffering from heat exhaustion, stop what you’re doing and move to a shaded or air-conditioned area immediately, advises Michael Bergeron, Ph.D., the heat, hydration, and research advisor to Major League Soccer.
Remove any excess clothing, lay flat on your back with your legs elevated, re-hydrate, and wait at least a day before working out again.