We
’re into the “dog days” of summer. The calendar may say that
fall is approaching, but the thermometer says otherwise. You may be
asking yourself “is it safe to exercise in hot weather? When is hot
too hot?”
We’re into the “dog days” of summer. The calendar may say that fall is approaching, but the thermometer says otherwise.
You may be asking yourself “is it safe to exercise in hot weather? When is hot too hot?”
If you’re going to exercise in a warm environment, it is important to understand how the human body reacts to external heat, and how it gets acclimated.
Our bodies have an internal thermometer. A “normal” core temperature for a human is 98.6 degrees. As people, we must regulate and maintain this, regardless of what the temperature outside might be. The external temperature could possibly have a profound effect on the core temperature, if it is not properly managed.
It takes several weeks for the body to adjust to being active in the heat. Eventually, systemic changes take place. Blood flow becomes more effective; circulation to the skin improves; heart rate slows down (the heart pumps the blood more efficiently); your body cools down more easily; you sweat more (also aids in cooling the body); and your body holds on to the electrolytes due to increased ability to absorb water faster.
Dehydration is one of the most common effects of heat on a person’s system. Dehydration is caused when the body loses too much water content and essential body salts. Minerals (electrolytes) such as sodium, potassium, calcium bicarbonate, and phosphate are essential for proper bodily tasks.
Water is the most important nutrient in the body. It comprises 70 percent of muscles and 75 percent of the brain. Therefore, it would stand to reason than losing too much fluid is detrimental to one’s health.
Exercising in hot weather is safe as long as proper precautions are taken. It is important to understand the factors that affect heat loss, and the warning signs for heat distress.
There are many factors that affect heat loss, among them: body size, body composition (lean body mass/ fat mass ratio), fitness level, outside temperature, and even clothing. Remember, dark-colored clothing absorbs heat, while light colored clothing reflects it.
During exercise, one of the major avenues of heat/fluid loss is sweating. When the body’s core temperature goes beyond its “set point,” or its basal temperature, the body responds by perspiring. As the sweat evaporates, the skin cools. However, if the outside humidity is too high, or your clothing does not allow moisture to escape, the risk of heat-related illnesses increases.
Keeping hydrated is crucial when working out, or playing sports in the heat. Before exercising, drink at least two cups of water one to two hours prior. Drink another two cups 15 minutes before you begin.
During your activities, drink six to eight ounces of water every 15 – 20 minutes. If you wait until you are thirsty, it’s too late; you are already dehydrated.
Afterwards, drink plenty of water to replace the fluids you have lost. Water is the best way to replenish what you have lost. Electrolytes can easily be restored into your system via diet with foods such as non-fat dairy products, bananas, oranges, grapefruits and spinach.
With proper precautions, and exercising wisely, there is no reason to stop having fun in the sun. Enjoy the heat and be sure to drink plenty of fluids.
Karen Frost is the Wellness Director for Gold’s Gym of Morgan Hill. She holds a Master of Arts degree in Physical Education, and is certified by the American Council on Exercise as a Personal Trainer and a Lifestyle and Weight Management Consultant.
