(Spoiler: they can’t). And just the other day I decided to go for an 8 km run on a day in the high 30s (that’s way over 100 if you’re in the US), and halfway through the run, it felt like my entire body was converting into heat. Well, turns out that’s really, really dangerous.
My dad’s a runner too, and once during a marathon on an extra-hot day, the guy just passed out and opened up his knee all over the asphalt. That’s what heat exhaustion and heat stroke does. When I made it halfway through my run, and suddenly it felt like my insides had become nuclear fission, I thought, Christ, am I going to pass out too? I ran under some shade and slapped some water down my throat. Still no change in temperature. Uh oh.
Luckily, there was enough shade down a stretch of sidewalk that I could get my temperature under control, but still. Not good. It wasn’t full-on heat exhaustion, but it was the early signs.
Here’s the twin heads of the heat hydra: heat stroke is the big brother of heat exhaustion, and it happens when the parts of your body that regulate temperature (specifically, your hypothalamus and associated functions) become overwhelmed by too much heat. This is the life-threatening one, the one where your internal organs start shutting down if it goes on too long.
If your skin has gone dry, you’ve stopped sweating, and you’ve started breathing rapidly, that’s the early signs of heat stroke. Next you’ll start speaking jibberish, having muscle cramps and possibly seeing hallucinations, but hopefully you or someone else has called 911 by then. Because if you have heat stroke, you’re going to want real medical attention.
Heat stroke’s baby brother is heat exhaustion, and that guy can sneak right up on you. You don’t see or feel it coming.
Heat exhaustion happens when your body is generating more heat than it can get rid of. Symptoms include heavy sweating, headaches, pale skin, dizziness, passing out (big sign there), cramps and extreme thirst. It usually happens when you’re not drinking enough fluids, or the fluids you are drinking don’t have enough salt. And once you’re in heat exhaustion, you have to get out of it as soon as possible by cooling down in a shady place or in an air conditioned building, before it becomes heat stroke.
Or you can try to avoid it altogether.
One way is to just not expose yourself to extremely high temperatures in the first place. Wait until after high noon and go running in the afternoon to bypass the Savannah heat of midday.
And stay hydrated. The number one cause of heat exhaustion is not replacing fluids fast enough. But what about the admonishment that the fluids need enough salt? Well, for that, Livestrong’s Christina Hall recommends sports drinks. “Sports drinks and other electrolyte-enhanced beverages replace electrolytes and prevent dehydration by maintaining a mix of water, sugar and electrolytes. Drinking a sports drink will also help to alleviate risks from physical exertion by lowering and maintaining a decreased body temperature, which will keep you from sweating the replaced electrolytes out.”
She also recommends eating an electrolite-rich diet: “Consume a diet that is high in foods that replenish your body with a needed supply of the three most commonly depleted electrolytes — calcium, magnesium and potassium.” This helps your body to metabolize minerals faster, which will help you generate sweat better.
Beyond that, just stay smart. Wear light colours to reflect the heat, and run on the shady side of the road. And I know, I feel you: I love running in the sun too. But when I got to that corner and started thinking about whether or not I should look for a comfortable place to pass out, I realized how serious that heat stuff can be.
Better to stay safe and stay cool.