Scientific panel aims to reduce incidence of heat illnesses, heat stroke during preseason practices for high school players

Aug 30 2005

New guidelines from the American College of Sports Medicine (ACSM) emphasize fluid replacement and acclimatization to the heat, as well as practice uniform and other modifications in order to reduce the risk for heat exhaustion and exertional heat stroke in young football players.

The guidelines are outcomes from the newly published ACSM Roundtable Series: Youth Football: Heat Stress and Injury Risk.

Heat stress and dehydration continue to be problematic for young football players, particularly during preseason practices. Between 1995 and 2001, 21 high school football players died of heat stroke, and there have been other fatalities since this time. Two severe incidents, one resulting in death, occurred as recently as last week in Oklahoma and Texas, respectively. The overwhelming majority of serious heat illnesses occur in the first four days of preseason football practice (especially on the first and second days), when players are not acclimatized to the heat, the intensity/duration of practice, or the uniform.

In an attempt to curtail heat illnesses and heat-related deaths among young football players, ACSM convened a panel of experts to examine hydration, environment and other factors which can cause players to overheat. The recommendations are designed for coaches, parents and players to follow during preseason football practices, already in progress at high schools across the nation.

“We’re finding that the primary reasons for a football player to overheat on the field are intensity and duration of practice, the environment and the uniform,” said Michael F. Bergeron, Ph.D., FACSM, Chair of the Roundtable panel. “There’s also a variety of problems that a football player can have related to sweat losses and consequent fluid and electrolyte deficits. That can range from feeling a little ‘off,’ to not performing well, to heat cramps or heat exhaustion—or if it were unattended, even heat stroke. If a player’s body temperature reaches a certain threshold and they no longer have the capacity to regulate temperature, it can run away from them and readily lead to death.”

Among its recommendations, the panel suggests that high school football players and their parents be aware and understand the impact of HEAT:

1) Hydration
2) Acclimatization
3) Environmental Conditions
4) Treatment

• Large sweat losses, insufficient fluid intake and consequent fluid deficits increase the risk of hyperthermia and heat injury. Players should begin practice well hydrated, well rested and well nourished, with a normal resting body temperature. Every practice should include regular fluid breaks designed to replace the majority of sweat loss at least every 30 to 45 minutes. Breaks should be more frequent as heat and humidity rise.
• Fluids should be chilled and easily accessible. Players should use shade whenever possible. Body weight measurements should be taken before and after practice to help determine the amount of fluid that needs to be replaced. Sports drinks have an advantage over water, as they replace electrolytes such as sodium (which is lost in sweat), as well as carbohydrates for energy.

“Young athletes are coming to practice dehydrated, they’re getting more dehydrated as practice continues, and they’re progressively even more dehydrated on each succeeding day of practice. Athletes need to pay more attention to hydration in earnest, and make a stronger effort to be more hydrated at the start of practice, to drink regularly during practice, and to recover sufficiently from each practice so they can start the next day adequately hydrated,” said Bergeron.

Environmental Conditions

• The length of each practice session should not exceed three hours (including warm-up, conditioning, instruction, breaks, and cool-down) and should be modified appropriately, in accordance with the environmental conditions (heat, humidity, and exposure to direct sunlight) in order to effectively reduce the associated risks and improve the overall safety for young football athletes.
• Players should not use stimulants, including ephedrine and high-dose caffeine often found in dietary supplements or “energy” drinks.

Acclimatization

• When players report to camp, they generally are not as well conditioned and acclimatized as college players, which may contribute to earlier fatigue and greater risk of injury.
• The body needs up to 14 days of progressive activity in the heat to undergo the physiological changes that allow for safe and sufficient acclimatization (the first three to five days are the most critical).
• Players should practice in light-colored clothing, and wear shorts with helmets and shoulder pads only (not full equipment) or shorts only (with all protective equipment removed) for the first week of practice. Helmets should be removed whenever possible (during instruction).

“Coaches and athletic trainers should be aware of the fact that the football uniform itself adds tremendously to the heat burden on the athlete. So frequent rest breaks where athletes are allowed to take off their helmet, take off their shirts and so on, would help mitigate some of those problems,” said W. Larry Kenney, Ph.D., FACSM, an advisor to the panel.

Treatment (Monitoring/Emergency Readiness)

• Players should be closely monitored by the team support staff (including athletic trainers) for signs and symptoms of developing heat-related injury during practice.
• Any changes in player performance, personality or well-being should be sufficient reason to stop practice immediately for that individual. Teams should use the “buddy” system, by assigning two players to help monitor each other.
• If exertional heat stroke is suspected, players should be stripped of equipment and immediately cooled in a tub of ice water until emergency personnel can assume care and evacuate the athlete to the nearest emergency facility.

Parents, players and coaches should all be aware of the warning signs and symptoms of dehydration and heat illness

• Thirst
• Irritability
• Headache and dizziness
• Muscle cramping and unusual fatigue
• Nausea and/or vomiting
• Hyperventilation
• Confusion and change in personality

According to Kenney, "the three main things that athletes can really remember to reduce the risk of heat-related illness are acclimation, hydration and common sense."