Heat Related Illnesses

Humidity: Humidity is the amount of moisture that is in the air. Why is this important when it comes to heat illness? Because the rate at which perspiration evaporates is strongly influenced by humidity. Sweat becomes an insulator when it cannot evaporate.

Relative humidity: Relative humidity is a measurement of the moisture in the air based on the amount of water in the air and the maximum amount that could be in the air. This is used to calculate the heat index! The heat index is the measure of how hot it actually feels when the relative humidity is combined with the air temperature.

Heat Index Chart:

Psychrometer: A Psychrometer is an instrument used to measure relative humidity This combines the air temperature with the humidity to come up with the relative humidity.

Heat Cramps: Heat cramps are muscle spasms resulting from dehydration. What causes heat cramps? Dehydration or an imbalance of water/electrolytes in the body. Signs & symptoms: muscle cramps, salty sweat, fatigue. Treatment: stretch/massage the area and hydrate

Heat Exhaustion: Heat exhaustion is a condition in which the body becomes dehydrated from water/electrolyte loss (imbalance). Signs & symptoms: fatigue, dizziness, profuse sweating, headache, nausea, vomiting, muscle cramping Treatment: put in shade, elevate legs, rehydrate, remove excessive clothing

Heat Stroke: Heat stroke is caused by an elevation in body temperature such that the body’s internal organs begin to shut down because of excessive heat. Signs & symptoms: dizziness, NO SWEATING, confusion, unconsciousness, seizures, decreased blood pressure Treatment: call 911, immerse in ice bath, cool down!

Preventing Heat Illness: 1. weigh yourself before and after practice. Loss of 3% of body weight should be noted. 2. if you lose more than 3% body weight then check for signs of heat exhaustion. If you lose 7% body weight you should be sent to see a doctor. 3. check body fat %. Athletes with low body fat % are more susceptible to heat illness. 4. check the weather or take psychrometer reading before practice/ games. 5. use heat index to modify practices/games. Look out for symptoms of heat illness.

Preventing Heat Illness: 6. acclimate to weather. It could take up to 2 weeks to fully acclimate. 7. be aware of clothing/uniform choices based on season, weather, and area. 8. change sweat soaked shirts throughout practice. 9. avoid caffeine, alcohol, and carbonated beverages. 10. replenish every pound lost with 20 oz of fluid after practice/games. 11.thirst is not an indicator for dehydration. By the time that you are thirsty, you are already 2% dehydrated!

Preventing Heat Illness: 12. Drink fluids before exercise…20oz 2-3 hours before, and 10oz 10-20 minutes before. 13. Always have water available. Drink 10oz of fluid about every 15 minutes of exercise. 14. Cold water empties the stomach faster than warm water 15. Monitor the color and volume of urine. Light colored urine is normal, dark colored urine means dehydration. (vitamins etc can alter this) 16. Someone with a fever is more susceptible to heat illness because the body’s core temperature is already increased.

Preventing Heat Illness: 17. drink plenty of fluids before, during and after practice to replenish fluid loss. 18. some sports drinks such as gatorade can provide an advantage to water because they contain electrolytes (salt, potassium, chloride) as well. 19. salt can be added to water to help hydrate. 20. well balanced diets can prevent heat illness

Effect on Performance: How does dehydration effect sports performance? As dehydration increases, there is a gradual reduction in physical and mental performance. There is an increase in heart rate and body temperature, and an increased perception of how hard the exercise feels, especially when exercising in the heat.

Effects on Performance: Studies show that a loss of fluid equal to 2% of body mass is sufficient enough to cause a detectable decrease in performance. A loss of 2% bodyweight causes an increase in perceived effort and can reduce performance by 10-20%. A fluid loss exceeding 3-5% bodyweight reduces aerobic exercise performance noticeably and impairs reaction time, judgement, concentration and decision making - vital elements in all sports.