Growing up as an athlete in Louisiana, I was one of many teenagers who took to the football field for summer two-a-day practices. In the nearly tropical summer heat and humidity, we would practice and play in triple-digit temperatures – almost always in full padding. Between sessions, my teammates and I sometimes stood under cold showers for 15 minutes, wearing our full uniforms, just to try to cool ourselves down. It was in those temperatures that a player I knew collapsed and died on the field from exertional heatstroke, or EHS.

EHS is a severe form of heat-related illness and a medical emergency that can result in brain and other organ damage, or even death in some cases. According to a 2015 article in The Journal of Applied Physiology, EHS ranks as the third leading cause of sudden death in high school athletes.

EHS can occur in otherwise healthy individuals and is different from classic heatstroke, which usually affects those who are very young, elderly or have pre-existing medical conditions. Athletes and soldiers whose uniforms require heavy gear are especially vulnerable.

Treatment for EHS has evolved very little over the centuries, essentially relying on external cooling methods. Water immersion, an earlier version of cold water immersion (today’s first line treatment for EHS), was described by the Greek physician Hippocrates in 400 B.C. But even as today’s young athletes and their parents are becoming better informed about the risks of concussion and dehydration out on the field, many believe that heat is merely uncomfortable and do not recognize the dire risks it can present.