Exercise hot or cold to burn calories?

I don’t have any problem exercising in the cold, but when the weather gets to hot I get exhausted very quickly. Is that because it is taking energy to maintain my body heat? Do I burn calories faster in the heat or in the cold when I exercise?

Do you drink water while you exercise?

I think you are getting exhausted because your natural cooling system is getting overwhelmed and it is your body’s way of telling you to slow down. It has little to do with how many calories you are burning from exertion. I may be wrong but I would wag that calorie burning during exercise is faster in very cold weather both because you can exercise for longer periods of time before getting too hot and all that waste heat represents energy as well and it can bleed off into the air easier. This assumes other things being equal of course.

But why would my body be telling me to slow down if I’m not running out of energy? How could I run out of energy faster if I’m not burning calories faster? Does it take energy to sweat? The physics answer is obvious. If it is cold out it will take more energy to maintain your body temperature therefore you must be burning more calories when it is cold. Unfortunately, it is not a physics problem it is a metabolic problem. Is there something in the human metabolism that could require more energy when it is hot? I know that seems counter intuitive from a chemistry prospective, but it must require energy to keep the body cool.

Firstly, read the first sentence of Shagnasty’s post. The heat is not what is making you run out of puff per se, your body is telling you to stop because you are overheating.

Secondly, except at a low value for cold and a low value for effort, you will not burn more calories just to keep warm when exercising in cold weather. Your body is quite inefficient. A whopping 60 percent of the calories you burn to exercise go to heat.

Thirdly, no it does not require energy to cool the body (at least, nothing significant). Heat is just lost through radiation and evaporation. All your body has to do is sweat, and allow blood into surface vessels, neither of which takes any significant energy to do.

I’m from a sub-tropical climate. I’ve run long distances in temperatures (and humidity) of 90 and well above. If you’re acclimatized to heat (people who live in hot climates can sweat more) and you keep fluids up, you can exercise in heat without difficulty.

Yeah, you’re overheating all right. Why do muscles exhaust easier when they get too hot? Possibility: the hotter you are, the more you sweat and the more blood is shuttled to the surface of your skin to cool your body through conduction. This would leave less blood for the muscles to use, and the shuttling of blood to the skin would cause blood pressure to drop, forcing the heart to beat faster to keep up. Interesting question…

I read once (maybe 25 years ago) that both hot and cold weather upped the calorie consumption compared to mild weather. The feeling was, hot = higher metabolism (thus more calories burned) and cold = your body is forced to burn extra calories to just keep you alive. I’d put my dough on cold weather to burn more, FWIW. And it’s much more pleasant.