Do you burn more calories walking in the heat or cold? Many factors influence how many calories you burn, even temperature. Cold and heat can raise calories burned, but neither is a good strategy for weight loss. Exercising in the heat and shivering in the cold puts extra stress on your metabolism.
Read more: Do You Burn More Calories Running in the Heat?
Hot Temps Burn More Calories
"In general, you burn more calories when you are hot because your cardiovascular system has to do more work to pump blood. Your heart works harder to pump blood to your muscles, which are using more energy," says John P. Higgins, MD, FACC, professor of cardiovascular medicine and sports cardiology at McGovern Medical School, UTHealth in Houston.
Working up a sweat is your body's way of cooling you down, according to the Cleveland Clinic. It may be a sign that you are burning more calories because, as Dr. Higgins explains, "your cardiovascular system is working harder to send blood to your skin to cool you down."
But the Cold Can Also Burn Calories
External temperature can affect your basal metabolic rate, according to the American Council on Exercise. Basal metabolic rate is the energy you need to keep up with breathing, maintaining a stable body temperature, digesting your food, making hormones and more. You're always burning calories, even when you are sitting still or sleeping.
But when you're cold, your basal metabolic rate increases, because your body needs to work harder to keep your body temperature up. That burns extra calories. In fact, just to raise your body temperature by one-half degree centigrade, your basal metabolic rate needs to increase by about 7 percent.
Your metabolic rate is how fast you burn calories to produce energy. When you take in calories from food or drink, your body combines those calories with oxygen to burn them. How many calories you burn under any condition, whether hot or cold, depends on your individual metabolism. The size of your body, your body composition and your age all affect the number of calories burned, per the Mayo Clinic.
Cold weather doesn't increase calories burned unless you get really cold and start to shiver, according to the ACE. Shivering is a sign that your body is working really hard to keep your body temperature normal. In some cases, shivering can burn through your sugar reserves for energy and burn up to 400 calories per hour. That is a lot of calories, but it leaves you drained and exhausted.
"To be sure, if you are shivering you also burn more calories, but most people exercising in the cold have proper cold-weather gear on and are not shivering, and they warm up fairly quickly," Dr. Higgins says.
The Best Temperature for Exercise
"You burn more calories when you exercise in the heat. However, the best range of temperature to burn fat and calories, and to exercise longer, is around 68 degrees, so I recommend that temperature," Dr. Higgins says. "The more intense you exercise, the more calories you burn. Exercising in higher temperatures, like 100 degrees, burns more calories from glycogen and less from fat."
A final thing to remember about exercising in the heat: You may burn more calories, but you also put a lot more stress on your body. The combination of exercise and heat can increase your body temperature into a range where you push past your body's ability to cool itself by sweating. This puts you at risk for a heat-related illness like heat exhaustion or heatstroke, according to the Mayo Clinic.
Read more: 8 Ways to Stay Safe and Cool During Summer Workouts
- John P. Higgins, MD, MBA (Hons), MPhil, FACC, FACP, FAHA, FACSM, FASNC, FSGC, professor of cardiovascular medicine, sports cardiology, McGovern Medical School, Houston, Texas
- Cleveland Clinic: “Breaking a Sweat: Why You Sweat and What It Says About Your Health”
- American Council on Exercise: “Resting Metabolic Rate: Best Ways to Measure It—and Raise It, Too”
- Mayo Clinic: “Metabolism and Weight Loss: How You Burn Calories”
- American Council on Exercise: “Do I Burn More Calories When It Is Hot Outside or Cold?”
- Mayo Clinic: “Heat and Exercise: Keeping Cool in Hot Weather”