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NEWS RELEASE

April 15, 2004
For immediate release

Contact:
Christa Dickey
cdickey@acsm.org
Jim Gavin
jgavin@acsm.org

SUMMER TEMPS HEIGHTEN HEAT INJURY RISK FOR ACTIVE PEOPLE
Know the Signs; Cancel or Delay Activity, Says Expert

ORLANDO – People moving their exercise regimen outdoors and athletes beginning training camp in the summer all have a potentially dangerous injury risk in common: exertional heat stroke, a condition that raises body temperature to a level that interrupts organ functions, especially the brain. American College of Sports Medicine (ACSM) president-elect William O. Roberts, M.D., FACSM today said active people should take precautions, be particularly alert to their bodies when exercising in the heat, and poised to take action if signs develop. Additionally, activities should be canceled or delayed when it is too hot or it is hotter and more humid than expected.

Heat injuries most often occur when people exercise in hot and humid conditions they are not accustomed to or exercise harder than usual in high temperatures. The heat generated by the muscles is not removed by sweat evaporation from the body in humid conditions and rising body temperatures are the end result. Children and youth are at particular risk.

Dehydration plays a role in exertional heat stroke, as it limits the body's ability to regulate body temperature by sweating and/or skin blood flow. To minimize the potential for thermal injury, ACSM experts recommend water losses due to sweating during exercise be replaced at a rate close to or equal to the sweating rate. This can be accomplished by athletes weighing themselves before and after exercise.

Over-the-counter drugs and supplements, such as products containing ephedra, are known to raise the risk of heat illnesses. Supplements containing ephedra speed up the body's metabolic rate and counteract the body's ability to shed heat. Other risk factors include people with large body mass (and fat), and those with a reduced body heat storage capacity.

People who are not acclimatized to hot temperatures should refrain from intense workouts in the heat. Roberts recommends athletes expecting to train and compete in the heat:

• Get fit first in a cool environment
• Opt for the cool part of the day for intense workouts
• Monitor hydration
• Ensure extra salt intake early in heat exposure or if muscle cramping occurs
• Schedule daily heat exposure for at least a half-hour for two to three weeks to adapt to the environment

Finally, if an athlete collapses in hot summer temperatures or hot humid environments, exertional heat stroke must be ruled out by measuring a rectal temperature, says Roberts. Muscle cramping, disorientation, and exhaustion are among the symptoms, but Roberts says rectal temperature is the only measure that will make or rule out the diagnosis. Delays in diagnosis and treatment can be fatal.

"Think ‘Heat Attack!’ like you would react to a heart attack,” said Roberts. “Early recognition and immediate action is critical to the outcome of heat injuries. Oftentimes, these are not recognized in practice or on the field of play. Athletes suffering from exertional heatstroke need immediate treatment on-site and then should be transferred to the emergency room.”

ACSM’s Health & Fitness Summit & Exposition is going on now at the Renaissance Orlando Resort at SeaWorld. For more information on the event, or to speak with staff in the on-site press office, please call (407) 235-7247 (through Saturday, April 17).

The American College of Sports Medicine is the largest sports medicine and exercise science organization in the world. More than 20,000 International, National and Regional members are dedicated to promoting and integrating scientific research, education and practical applications of sports medicine and exercise science to maintain and enhance physical performance, fitness, health and quality of life.

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The American College of Sports Medicine gratefully acknowledges the following Health & Fitness Summit & Exposition sponsors: LifeFitness (Premier Sponsor), Gatorade Sports Science Institute, Gatorade, Reebok (Educational Partner), Amino Vital, Centers for Disease Control and Prevention, EAS, Lippincott Williams & Wilkins, BSDI, and SPRI Products, Inc.