NEW ORLEANS – Easing into the often hot and humid preseason significantly reduces high school football players’ risk of suffering from potentially deadly exertional heat illness (EHI), suggests a first-of-its-kind study being presented today at the National Athletic Trainers’ Association (NATA) 69th Clinical Symposia & AT Expo. Athletes in states that followed preseason heat acclimatization guidelines for secondary school athletics developed by an NATA-spearheaded Inter-Association Task Force were 55 percent less likely to suffer from EHI, researchers found.
Heat stroke is the most serious form of EHI, which is the leading cause of death among U.S. high school athletes, according to the Centers for Disease Control and Prevention (CDC). Heat stroke makes it difficult for an overheated body to cool down quickly, leading to seizures, coma and damage to organs.
The task force guidelines stress that athletes in all sports need to slowly acclimate during the first 14 days of the preseason (not counting days missed due to injury or planned rest) via: shorter practices, numerous rest breaks, keeping two-practice days to a minimum, requiring the presence of an athletic trainer during practice and games, and limiting and then slowly increasing the amount of equipment worn. Progressively adjusting to the heat is especially important during the first three to five days of summer practices, helping the athlete build up tolerance to the heat and improving exercise performance.
“Doing high-exertion physical activity for hours in the blistering heat while wearing equipment after a summer off without a chance to adjust is too much too soon for high school football players,” said Zachary Kerr, PhD, MPH, assistant professor in the department of exercise and sport science at the University of North Carolina, Chapel Hill. “It can lead to catastrophic consequences that are preventable when we’re proactive.”
The first to assess the real-world effectiveness of the guidelines, the study analyzed an estimated 2.6 million “athlete exposures” in about 120,000 high school football players from 48 states over 12 years. Researchers compared EHI events in eight states that were fully compliant with task force guidelines to the 40 that weren’t. They identified 190 cases of EHI, none of which resulted in death. There were seven EHI events in full-compliance states for a rate of .04 per 1000 athlete exposures, compared to 183 EHI events in states that weren’t fully compliant for a rate of .07 per 1000 athlete exposures. Factoring in other issues such as August temperature variations, they determined that mandating the guidelines was associated with a 55 percent reduction in EHI rates.
The eight guidelines-compliant states are: Arizona, Connecticut, Iowa, Mississippi, North Carolina, New Jersey, Rhode Island and Utah. Another 20 states partially complied with the guidelines. Researchers determined partial compliance was beneficial, but the risk-reduction was strongest in states with full compliance.
Signs of EHI include symptoms of dehydration (such as dark-colored urine), dizziness, headache, nausea, vomiting and a temperature of 104 or above. When EHI is suspected, the athlete should be immediately cooled in cold water. If the athlete is treated within 30 minutes of collapse from EHI, particularly heat stroke, there is a 100 percent survival rate, said Kerr.
“The study’s findings are dramatic,” said Kerr. “Clearly, state high school athletic associations should mandate these guidelines and provide the support that schools, coaches, and athletic trainers need to properly implement them.”