How hot is too hot to run? And how do you cope with extreme heat on runs?

I say 45 C is too hot to run.

Run indoors, don't run, run at the crack of dawn, hydrate well, stash water along your route, cut back distance and/or intensity. Long workouts (or races) in the extreme heat are pointless and unhelpful. In fact, they are a net negative.

If you live in a place where it is literally hot for months (like FL/TX in the US) at a time you can and will adapt but you have to adapt slowly and not just running. You have to embrace the heat and be out in it regularly.

Run very early or late. Run less and avoid extreme heat.

I'm in Sydney - run early and schedule long runs for less humid days. Run shirtless and in split shorts, much cooler. Wear a hat.

anything close to or exceeding body temp and you can cool only by sweating. Skin must be exposed for it to work. Must be hydrated. Might not be enough to prevent core temp from overheating.

Summer time means lots of swimming and cycling for me. I'll run on a treadmill to keep the legs prepared for when it cools down and I ramp up the mileage.

Run naked!

First of all, I stick to certain rules, I try to choose a darkened place if possible. In addition, and importantly, I change my clothes for more airy ones, keep my pace and don't run before a satiating meal. Of course, in terms of hydration, I can hint that in addition to the usual isotonic drinks, I was once prompted by a more experienced runner to drink non-alcoholic beer (something with bubbles). And most importantly, I never overestimate my capabilities.

Apparently 70° will kill you. Nothing you can do about it, just whine on the social. Maybe start a podcast so everyone can literally hear your squeaky soprano .

Or, if it's on earth and summertime, or you live in a warm place, you could pull back on mileage and work up the distance as your body adapts,, but whining is easier.

It never gets too hot to run in any major population centre in Australia. Even on a 45 degree (celcius) day there are ways to avoid the heat.

As others may have mentioned, on hot days:

* run in the early morning

* run on a treadmill with air conditioning and a fan

* properly hydrate

* wear appropriate attire (split shorts, singlet - preferably not black)

Other tips:

* run on a loop course, and stash drinks and ice so that you can pick them up each time you complete the loop.

* use electrolyte tabs

120F I guess. Hottest I've ever run is 111 and 113 heat index (seperate occasions) To cope with extreme heat you slow down, reduce distance, and carry water.

Give your body enough time to gradually adapt to the heat (and humidity if that's relevant to your situation). The answer is probably very dependent on the person and their own heat tolerance (both physically and mentally).

I live in the southeastern United States. The heat and humidity here is absolutely brutal and can be very dangerous, especially if you're not careful or adjusted to it. I accept the heat and humidity and therefore am willing to spend lots of time in it, including running in it, yes even in the afternoon in middle of summer. But that tolerance is built up gradually over weeks or months. It's a high of 50 F today. If tomorrow I was transported to July here with a temperature of 95F and a dew point of 75F, I might have some issues just immediately running how I want in that. But as the season changes and I gradually adjust, I'll absolutely be running in that weather. Over 100F with a high dew point is when I'm going to try to run later in the evening (when it's a comfortable 90F haha). It's also worth noting, just like running in general, yes a big part is physical, but beyond a certain threshold it becomes also a mental challenge, which appeals to me.

My coworker, who is in his late 50s, also runs in the heat of the summer and has been all his life.

But if you're the person purposely avoiding being outside, you're not going out in it to hike, walk, yard work, or whatever, you probably shouldn't then be running in it either.

Also, you may want to check with a doctor.

It's the wet bulb temperature that matters.

At a wet bulb temperature of around 35°C (95°F), the combination of high heat and humidity in the environment makes it both hotter and more moist than the human skin. Under these conditions, the air is so saturated with moisture that sweat cannot evaporate efficiently from the skin. Evaporation is a cooling process, so when it's hindered, the body loses its most effective natural mechanism for regulating its internal temperature.

omnicalculator.com

Wet Bulb Calculator

With humidity and temperature you can find out the value of the wet-bulb temperature, and if it's any different from the normal air temperature.

Open link

Run in the forest where it’s permanently shaded

This also gets you away from all the nuisance vehicles swarming around like flies to meat

Answer is same as last year.

The world 🌎 is hotter then last year.

Answer is same as last year.

105 F (~40 C) is when I start questioning my decision to run in the middle of the day. If it is getting above 40 C I try to run early in the morning.

WTF is a Celsius 🦅

Use a real American temperature