NFHS Memorandum – Heat Acclimatization and Heat Illness



From:            Greg Elkins, M.D., Chair of the NFHS SMAC & Bob Colgate, NFHS Director of Sports and Sports Medicine             

Subject:         Heat Acclimatization and Heat Illness


As we head into the fall preseason, I want to remind everyone that it is critical to alert your member schools that this is the peak time of the year for risk of heat-related illnesses and deaths!  As we discussed at the recent NFHS Summer Meeting in San Antonio, data from the National Center for Catastrophic Sport Injury Research (NCCSIR) shows that for the period from 2011-12 to 2020-21 there were 20 heat stroke deaths in high school athletes in that 10-year period with 14 of those occurring in July/August and 17 in football.  That data mirrors the previous 10-year period. 


Repeated alerts are appropriate over the next few months as temperatures may wax and wane.  Just before a predicted “heat wave” coaches and school administrators are best reminded through emails and social media of the importance of activity and practice modifications.  In addition, remember that this is not just a football issue.  Any student participating in an outdoor sport in the heat is vulnerable to heat illness, including participants in activities such as marching band, cheer and also volleyball players practicing in a hot gym. 


With increased use of Wet Bulb Globe Temperature (WBGT) devices, it is important that state associations continue to educate their member schools on new policies and procedures they have put in place on heat acclimatization and heat illness.  School administrators, athletic directors, coaches, parents and students should also be made aware of the following resources from the NFHS and the NFHS Sports Medicine Advisory Committee (SMAC): 


NFHS “Heat Acclimatization and Heat Illness Prevention Position Statement


NFHS “Position Statement and Recommendations for Maintaining Hydration to Optimize Performance and Minimize the Risk for Exertional Heat Illness


NFHS “Heat Illness Prevention” Online Course from


NFHS “The Collapsed Athlete” Online Course from


Other resources are available on the following link to the NFHS Sports Medicine web page including those from the National Athletic Trainer’s Association and the Korey Stringer Institute:


It is crucial that the heat acclimatizing guidelines are strictly followed as published by the state association, with extra vigilance during the first 3-4 days of any transition or acclimatization period.  This is the time when our students are most vulnerable to the heat.  


Thanks as always for what you do for our students across the country! 


Greg Elkins, M.D. 

Chair – NFHS Sports Medicine Advisory Committee