How Hot Is Too Hot to Exercise Outside?
If you’re into fitness, you probably love being outside and staying active. But once that summer heat kicks in, it’s super important to think about your body’s safety and how it's handling the temps.
As The Washington Post puts it: “The stakes are high. The consequences of a too-hot workout range from feeling thirsty to death,” said Clare Minahan, a sports scientist at Griffith University in Australia.
The tricky part? It’s not as simple as just checking the temperature to know when it’s too hot to work out outside. So… is there an easy rule of thumb to follow?
Honestly, I’m kind of surprised this even needs to be asked—the answer feels so obvious to me.
The rule is super simple: just listen to your body and pay attention to how you feel.
There’s no magic number on the thermometer that tells you when it’s safe or not to work out outside.
Plus, the way our bodies handle heat and cold is different for everyone. So, for some people, working out when it's 77°F (25°C) might feel just right, but for others, it could be way too much to handle.
The human body is an incredibly intelligent system. It’ll let you know when something’s off—if you’re overheated, uncomfortable, or just not feeling right. That’s your sign.
If just being outside in the heat already feels uncomfortable before you even start working out, then yeah, that’s your body saying: “Don’t do it.”
To the hardcore fitness folks who try to power through the heat no matter what—pushing past thirst, heavy breathing, or a pounding heart—I get it, you’re driven. But seriously, don’t punish your body like that.
Unless you genuinely feel great in the heat, and your body’s adapted or stays cool easily, you probably shouldn’t be training in high temperatures.
After 32 years of working out—including 10 years of competitive bodybuilding—and now at 45, I can tell you this with total confidence: your body doesn’t care about your fitness goals or PRs. Its number one priority is survival, and it’s really good at it.
So respect it. Treat your body with care, and it will reward you with longevity.