How to Exercise In the Heat
Learn how to keep cool when you’re exercising in hot conditions.
Ben Greenfield
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How to Exercise In the Heat
If you tuned into the recent New York City Triathlon, you may heard that there were many heat-related illnesses during the race, and even one tragic death. During the 2007 Chicago Marathon, runners were rerouted to a city park and instructed to stop running, since the heat was too intense to ensure runner safety. But even if you don’t plan on doing a triathlon or marathon in hot weather, a high temperature outside or in the gym can make exercise uncomfortable, inhibit performance, cause dehydration, and leave you feeling literally and figuratively under the weather. In this article, you’ll learn how to keep cool when you’re exercising in hot conditions.
What Happens to Your Body in the Heat
As soon as you get into the heat and begin to exercise, you force your body to circulate blood out to the skin, where it can be cooled. But this circulation to your skin can draw precious, oxygen-delivering blood away from your working muscles, and also lower the amount of blood your heart can pump with each beat. In addition, you’re also losing blood volume as you lose fluid in sweat, and this places additional demand on an already stressed heart.
As blood becomes a precious commodity and your heart is forced to work harder, your heart rate goes uncomfortably high, your breathing becomes more difficult, your blood pressure drops, and your core temperature rises. Eventually, you reach a point where your body sends a message to your brain to stop, and at that point, exercise goes from being uncomfortable and difficult, to simply impossible.
How to Stay Cool in the Heat
So what can you do about this loss of blood volume and increase in body temperature? Here are 5 solutions:
1) Train your body to maintain a higher blood volume. Also known as “heat acclimation,” the process of training your body to have more blood involves a combination of consistent training and heat exposure. Gradual exposure to exercising in hot conditions is one of the best ways to do train your body to heat acclimation. For example, start with 10-20 minutes of jogging, bicycling, or brisk walking in the afternoon heat, and add just 2-5 minutes each day as the heat becomes more tolerable. When you combine this with drinking big gulps of water whenever you begin to get thirsty, your body learns to increase blood volume to help you cool.
2) Increase your sweat rate. Did you know that very fit individuals and athletes produce more sweat? This is an enhanced cooling mechanism that is developed during heat exposure. I’ve personally found that a very good method for teaching your body to sweat more is to visit the steam room or sauna and simply sit for 10-20 minutes. Two to three weeks before I’m about to do a triathlon in hot weather, I’ll increase my steam room or sauna time up to 45 minutes, but this can be very taxing to your body, so be careful!
3) Decrease the amount of salt produced in your sweat. Not only do you sweat more as you get fitter and increase heat exposure, but you also lose less salt in your sweat! Your body actually learns to hold on to the precious sodium that you need for muscle contractions. While gradually becoming accustomed to hot exercise conditions, your body will automatically decrease the salt you produce in your sweat. You can also try to limit sodium intake during exercise. As you learn to live and exercise with lower salt intake, your body begins to excrete less salt.
4) Increase salt store availability. If you’re planning on going out to exercise in the heat for a long period of time, such as competing in a hot weather marathon or triathlon, you may need to salt your food for the last few days prior to your event. But this is really only necessary if you’re already on a low-sodium diet. By adding a little extra salt to each meal, or consuming electrolyte tablets that dissolve in water, you can give your body extra sodium stores to rely on during exercise.
5) Keep your core temperature cooler. Of the 5 heat management solutions, this is the most important, since you’re going to get hot no matter what! There are many strategies you can implement to keep your core temperature cool. Here are some of the most effective:
A) Dump water on your head and face. Whether from a fountain at the gym, a hose outside your house, or an aid station during a race, water splashed on your body can help with evaporative cooling. It will also give you a refreshing feeling that can override the overheating message your body is sending to your brain. The colder the water, the better!
B) Wear clothing that breathes. Exercise clothing that is designed for hot weather exercise is made of fabric that wicks away sweat and allows for your skin to breathe. A cotton t-shirt will not accomplish this effect, and may make you feel even hotter. Instead, look for synthetic fabrics specifically designed for exercise in hot conditions, such as polyesters, micro-fibers, and even ultra-thin wool.
C) Drink. The best and easiest way to maintain blood volume is to drink water that is as cold as possible whenever you become thirsty. Do not wait until several minutes after you’ve become thirsty to drink. If you have a long run planned, such as when you’re preparing for a marathon, consider carrying a water bottle with you, or running small loops near your house or a park where you can drink water often.
D) Use ice. Not only can ice help keep water cold during warm weather exercise, it can also be shoved down the front or back of your shirt, or, as is my habit during the Ironman World Championships in Hawaii, down the back and front of the legs. In addition, you can chew on ice or drink cold slushies to cool your core, as well as wear specially designed arm cooling sleeves, vests, and gloves!
E) Limit sun exposure. If you’re exercising in the heat, try to stay under trees, near fences, behind buildings, and in as many shady spots as possible, since direct sun exposure can significantly affect your body temperature.
Ultimately, the human body is incredibly able to adapt to hot conditions, but it needs gradual exposure to the heat and adequate water – plus, the strategies I described above for an added advantage..
If you have more questions about how to keep cool during exercise in the heat, share them below in Comments and on the Get-Fit Guy Facebook page!