Heat Illness - What is it and how do we prevent it?
Chris Wiedmann, ATC
UnityPoint Health - Des Moines Athletic Training Services
Hyperthermia, or Heat Illness, is a condition in which the body temperature is elevated. This can affect performance, and in some instances, pose a very serious health risk.
Each year, exertional heat stroke results in thousands of emergency room visit, hospitalizations, and lost time from practice and play nationwide.
Football may get a majority of the attention, but every sport is susceptible. Any sport with a high air temperature and humidity can become dangerous. Even a gymnasium without air conditioning can become very hot and humid, putting those athletes at risk. The better prepared the student athlete is before heading into his or her sport, the less likely they will be to suffer from these symptoms.
While proper hydration will not necessarily prevent exertional heat illness, it will decrease the risk.
Dehydration occurs when a person loses more fluid than he or she drinks. When this mismatch occurs, it becomes more difficult for the body to function properly, leading to early fatigue and an increased risk for heat illness.
Being properly hydrated is one of the easiest ways for athletes to ensure optimal performance and lower the risk of heat illness. Dehydration can impair athletic performance and make it more difficult for the body to cope with exercise in a hot and/or humid environment. Because students differ in body size, sweating rates and training regimens, it is difficult to recommend a "one-size-fits-all" hydration approach.
Here are some signs/symptoms of dehydration:
- Muscle cramps
- Dry lips and mouth
- Dark colored urine (should be clear or light yellow)
Here are some early signs/symptoms of heat injury to watch for:
- Deterioration in performance with signs of struggling, moving more slowly, and/or bending over with hands on knees
- Pale or bright-red flushing of the skin
If these signs/symptoms of heat injury occur:
- Remove the athlete from play and immediately move him or her to a shaded or air-conditioned area.
- Remove excess clothing and equipment.
- Have the athlete lie comfortably.
- If the athlete is not nauseated or vomiting and is able to drink, give cold water or a sports drink. If the athlete is unable to drink, the Emergency Medical System should be activated.
- If a rapid improvement is not seen with the interventions as above, activate the Emergency Medical System for transport to an emergency facility.
- The athlete should not return to physical activity until given clearance by an appropriate health care provider.
The goal of any practice is to challenge the athlete, which often results in him or her being fatigued. However, there are things to look for that may indicate more severe distress than just being exhausted. Recognize the more serious signs of exertional heatstroke.
Watch for these serious signs:
- Severe fatigue
- Obvious behavioral changes and/or other central nervous system problems such as confusion, loss of consciousness or seizures
If you see these signs, the activity must immediately stop and initiate rapid full body cooling while the Emergency Medical System is being activated.
For an athlete with exertional heat stroke, immediate medical treatment and rapid cooling can prevent serious illness or death. The first choice of immediate treatment is submerging the athlete in an ice-water filled tub. If an ice-water filled tub is unavailable, cold wet towels rotated frequently, and ice bags placed on the groin and armpits should be used for cooling.
The majority of heat-related injuries occur during the first few days of practice, from doing too much, too fast. Many high school athletes have a Superman complex and believe they can't, or won't get hurt. For this reason, it may be challenging to convince students that proper hydration is an important component of staying healthy. An easy way to determine sweat loss is to record the difference in body weight before and after exercise. It doesn't take much dehydration to affect performance. Losing even as little as 1 ½ -2% of body weight can take a toll on performance by causing fatigue and affecting physical and mental skills. Students should drink 16-24 oz. of fluid for every pound lost during exercise to achieve normal fluid levels within 6 hours of stopping activity. Fluid should always be readily available for students before, during and after all workouts, practices and competitions. For most athletes, the ideal replacement fluid is water. It's quickly absorbed, well-tolerated, an excellent thirst quencher and cost effective. While water is always an excellent choice for hydration, a properly formulated sports drink can provide some additional benefits. Most sports drinks contain a 6 to 8% carbohydrate solution and a mixture of electrolytes. The carbohydrate and electrolyte concentrations are formulated to allow maximal absorption by the gastrointestinal tract.
What's in a Sports Drink?
- Sodium: Sodium is the most critical electrolyte lost in sweat and plays an essential role in maintaining fluid balance. Once in the bloodstream, sodium helps maintain blood volume. That translates into a lower heart rate and greater blood flow to muscles and skin, which is important in helping sustain performance.
- Carbohydrates: Carbohydrates are the body's first choice for fuel, and consuming them during exercise helps fuel working muscles. Different types of carbohydrates found in Sports Drinks stimulate fast absorption by the gastrointestinal tract.
- Flavor: In many cases, the primary advantage of sports drinks may be that the flavor will be more likely to encourage greater consumption. Thirst is the body's defense against dehydration, and the combination of flavor and electrolytes encourage students to drink.
What not to drink
- Energy drinks are not the same as sports drinks. They are popular, but they are not designed to re-hydrate athletes during activity and should not be used in such circumstances. There is no regulatory control over energy drinks, thus their content and purity cannot be ensured.
- Fruit juices with greater than 8% carbohydrate content can result in a bloated feeling and abdominal cramping.
- Carbonated beverages and soda may cause an upset stomach or a bloated feeling.
An athlete will often show early signs and/or symptoms of developing exertional heat-related distress. If these signs and symptoms are promptly recognized and the athlete is immediately and appropriately treated, serious problems can be averted and the athlete can often recover, and return to activity when signs and symptoms have fully resolved.
The goal of hydration is to maintain normal hydration status, avoiding both dehydration and over-hydration. This is accomplished by drinking gradually and periodically before, during and after exercise. Water should be readily available at all times and access to water should never be restricted. Students can follow their hydration status by weighing in before and after workouts.
Recognize early signs of distress and developing exertional heat illness, and promptly adjust activity and treat accordingly. First aid should never be delayed.