BY DAVE L. MARSHALL, M.D.
Medical Director, Sports Medicine Program at Children’s Healthcare of Atlanta; Clinical Assistant Professor, Department of Pediatrics, Emory University School of Medicine.
From recreational activities to free-play to team sports to camps, outdoor activities in the south during the late summer months have one thing in common — the heat.
Heat-related illness is responsible for thousands of emergency room visits. Heat injury can range from mild heat cramps to heat stroke and death. It’s always concerning when I get a call from an athletic trainer, coach or parent telling me a child had to go to the hospital to be treated for dehydration or heat illness, because these conditions are largely preventable.
Armed with basic knowledge about how the body regulates temperature and simple hydration tips, parents can reduce the risk of children suffering heat-related illness.
How children’s bodies regulate temperature
Kids generate more heat during exercise than adults.
Children have a limited ability to send blood to the skin (which results in sweating and evaporative cooling — the most efficient way the body cools itself during activity), because they have less blood volume than adults.
Kids begin sweating later during exercise than adults.
Children absorb heat from the ground and pavement because they are closer to the ground than adults. This causes a child’s body temperature to rise more quickly than that of an adult.
Kids take longer to adjust to higher temperatures and humidity than adults. Children who are new to the South or who are out of shape should exercise for shorter, less intense sessions three to four times per week for two weeks to allow their bodies and temperature regulation response to adjust.
Keeping your child hydrated
Never rely on thirst. When a child begins to feel thirsty, he or she may already be one percent to two percent dehydrated.
Prehydrate. Thirty minutes before activity, have your child drink until he or she is no longer thirsty — then drink another eight ounces of liquid. Children weighing less than 90 pounds should drink five ounces after every 20 minutes of activity. Kids weighing more than 90 pounds should drink eight ounces every 20 minutes.
Water is the best drink for kids participating in activities lasting one hour or less. Children engaging in activities lasting more than one hour should drink a fluid with carbohydrates (sugars) and electrolytes. Sports drinks were designed specifically for re-hydration during exercise and contain the right amount of carbohydrates, about six percent to eight percent.
Fluids like fruit juice and soda contain a great deal of sugar and can cause cramping. Beverages containing carbonation and caffeine should be avoided, because the carbonation can make a child feel bloated and caffeine can speed up metabolism, which generates more heat.
Drink it, don’t pour it. Pouring cold water on the head or face may feel great when temperatures are high, but doing so does not improve hydration.