Running is an excellent way to stay in shape, burning more calories than many other types of exercise while giving you a heart-healthy workout. If you're not careful, though, you might end up getting too hot while you run. In some cases, overheating while running can even be a major health risk. Fortunately, it's usually possible to prevent or reduce the effects of overheating with a little careful planning.
Your body is designed to regulate its own heat, but there are limits to its capabilities. If the air temperature is above 55 degrees Fahrenheit, you'll start producing more heat while running than your body can get rid of effectively. The speed at which you overheat depends on the outside temperature and how fast you run, but eventually your body will reach the point that it begins diverting blood to the skin instead of the active muscles in an attempt to lose excess heat. This deprives your muscles of oxygen, causing them to slow down and produce less heat. If you continue trying to push yourself past this point, you can become significantly overheated.
There are some potentially serious problems associated with overheating while running. Dehydration is a major concern, since you lose water through sweat and respiration as your body tries to cool itself. Tripping hazards such as muscle fatigue, dizziness and even blacking out can occur as well if your body gets too hot. Heat exhaustion and heat stroke are also significant dangers as your body heats up, with the latter requiring medical attention as soon as possible.
If you pay attention, warning signs usually appear before you become too hot. Heavy sweating, muscle cramps, headaches and sudden feelings of weakness are early indicators of dehydration and overheating; if you experience any of these, slow down to a walk and drink water. Feelings of nausea or lightheadedness can also occur when you're getting too hot or are becoming dehydrated, as can sudden feelings of confusion or difficulty forming coherent thoughts.
If you start to feel overly hot, stop running and reduce your speed to a walk so your body can start cooling itself down while your breathing and heart rate return to normal. Drink cool water while you walk to rehydrate yourself and cool your body down. If you feel worn out or lightheaded, stop walking once your heart rate slows, and relax in a cool, shaded place if possible. Eat salty snacks such as salted nuts or crackers or drink an electrolyte-rich sports drink to help restore vital salts that will assist your recovery.
Prevention plays a large part in staying safe while running on warm or hot days. Start drinking water several hours before you start running to ensure that you're properly hydrated, and carry enough additional water with you so you can rehydrate with 4 to 8 ounces of water every 15 minutes while you run. Wear light mesh fabrics that won't trap heat next to your body during your run, and don't forget to put on sweat-resistant sunscreen to prevent sunburns. Avoid running in the hottest part of the day, scheduling your runs instead for the morning or late afternoon.
Born in West Virginia, Jack Gerard now lives in Kentucky. A writer and editor with more than 10 years of experience, he has written both articles and poetry for publication in magazines and online. A former nationally ranked sport fencer, Gerard also spent several years as a fencing coach and trainer.