When you are exercising or playing in the summer heat there are some things you need to watch out for to avoid serious physical consequences. First let’s simplify the factors that affect heat stress on your body during exercise: Air Temperature; Humidity; Wind Velocity; Thermal Radiation.
You must look at all four of the above factors to determine your level of risk for complications from heat. For example:
Exercising on a sunny 80 degree day with no wind creates more stress on your body than a cloudy 80 degree day with a 15mph wind.
90 degree days with 95% humidity have a much greater risk level than a 90 degree day with 40% humidity. Humidity impairs your body’s ability to sweat and cool itself.
Watch out for high temperatures with high humidity, if you add a sunny day to that combination and no wind you are really looking for trouble.
Problems caused by exertion in the heat:
Heat Cramps — Heat cramps are muscle spasms. These cramps result from dehydration and mineral losses during heavy sweating.
Heat Exhaustion — Your muscles during exercise are in competition with your skin for your limited blood supply. Heat exhaustion occurs when blood volume decreases due to fluid loss and when blood volume is diverted to your muscles so that they can continue to function which does not allow for your cardio vascular system to distribute an adequate supply of blood to the skin for cooling. Symptoms of heat exhaustion include dizziness, breathlessness, fainting, vomiting, cold and clammy skin, hot and dry skin, rapid pulse.
Heat Stroke — Heat stroke is a total collapse of the body’s ability to dissipate heat, and can be life threatening. Symptoms include rapid pulse, a body temperature over 104 degrees, confusion, hot and dry skin, and unconsciousness. Your best course of action is to cool the person as rapidly as possible. Place in a bath of cold water and contact medical personnel.
- Try not to exercise in the hottest parts of the day. Early morning or evening is better.
- Drink ample amounts of fluids. Thirst is not an accurate indicator of your need for fluid. When exercising in the hot and humid conditions, drink lots of water, but you may also want to add sports drinks into the mix to help balance electrolyte loss and provide carbohydrates that will help maintain blood glucose levels. Basketball on your driveway with the kids this summer can turn into a hot and sweaty exercise session for you and your kids. Keep in mind that sports drinks contain calories so stick to water if you are trying to lose weight. If you or your children are not fond of water pick up some of the new low calories sports drinks for both of you. I love the new Gatorade ad tag line: never underestimate the power of superior hydration. So drink, drink, drink to keep your body hydrated.
- Wear as little clothing as possible to allow heat to escape to the environment.
- Check the weather for heat, humidity, wind velocity and whether it is sunny or cloudy before you plan your outdoor activities.
- Seek a cool environment if you start to cramp, get dizzy, feel faint or feel nauseous.
Be safe in your outdoor activities and exercises this summer!