Tip #1 – Acclimate!
It takes your body a bit of time to get used to running in hot weather – about 2-4 weeks depending on your fitness level, training regimen, and the specific weather conditions. If you have a race coming up that’s in a warm weather area and you anticipate it being hot, you’ll likely want to do some of your training in the heat so your body can make the necessary adaptations.
Start with a slower pace and reduced intensity at first until you get used to the heat. Once you train regularly in it, your body can increase plasma blood volume which helps carry blood to the skin surface for cooling. Acclimating also means that you are able to sweat more efficiently and you lose less sodium in that sweat.
All this being said, train smart. If there is a major heat advisory out there, it’s not the time to try to prove your superhuman strengths with a mid-day long run. Train early in the morning or once it’s cooled off in the evening, or train indoors on the treadmill.
Tip #2 – Hydrate smart!
Drinking enough fluid is essential to staying healthy while exercising on warm days. If you’re working out for more than 60-75 minutes, it’s smart to take in fluid + electrolytes + carbohydrate. If you’re working out for less than 60 minutes, plain water is generally fine. If it’s a really warm day though and you’re out there less than 60 minutes, drinking an electrolyte beverage without carbs – like nuun tablets or something similar – might be helpful.
I’ve found some runners get nervous about drinking on runs, because many have seen media stories about overhydrating and getting sick from too much water intake (otherwise known as hyponatremia). That is a very real concern with serious consequences – however, dehydration is about six times more common in runners compared to hyponatremia.
The key is to drink enough to maintain the right balance; to prevent dehydration without risking hyponatremia. There’s no one guideline that fits all people for proper hydration. I can’t say drink x ounces per hour because we all sweat at different rates – person A may lose much more per hour than person B – so hydration recommendations really should be personalized.
My advice is to do a “sweat test” to see if you’re hydrating right on hot days – weigh yourself before and after a run in the heat (sans clothing). If you lost more than 3% of your body weight, you probably want to hydrate a bit more. If you gained weight, you should hydrate a bit less – you don’t want to overdo it. If you lost about 1-2% of your body weight, you’re probably in the sweet spot of proper hydration.
For example, if you’re a 150 pound athlete and you lost more than 4.5 pounds – you may want to hydrate more on your next run.
Even with a sweat test, above all – pay attention to your body’s cues for thirst (dry mouth, craving water) and overdrinking (sloshing, nausea) – and be sure to honor those cues.
And of course, if you’re training and you start to experience any warning signs of heat related illness or hyponatremia, stop and get help. Heat exhaustion may present itself with lightheaded, dizziness, confusion, muscle cramps, nausea/vomiting. Hyponatremia often presents with similar symptoms, and can dangerously progress to issues like seizure or unconsciousness.
Tip #3 – Remember the sodium!
Sodium is important for runs or rides lasting over an hour. Sodium recommendations are hard to give as generalized advice because the rate at which people sweat varies considerably, as does the concentration of sodium in a given amount of sweat.
As a starting point, the ACSM recommends that you take in about 500 to 700 mg of sodium per liter of fluid you drink during exercise that lasts more than an hour. If you’re a heavy salt sweater or you find yourself struggling in the heat, you may need a bit more.
Many commercial sports drinks will provide sodium in the 500-700 mg/liter range. If you’re curious about your sports drink, check the label. If it’s a standard 8 ounce serving, you can multiply the mg of sodium by 4.25 to tell you how much sodium would be in a liter of fluid. As an example, 120 mg per 8 ounces x 4.25 = 510 per liter.
If your beverage does not fall into this range, you might consider:
- Try a higher sodium sports drink product (for example, Gatorade Endurance contains 300 mg per 12-ounce serving and Skratch Labs has 285 to 380 mg per 12-ounce serving – depending on how you portion it based on their instructions)
- Try adding 1/8 a teaspoon of salt to your drink.
If you don’t use a sports drink, check the products you are using for fuel (like gels, blocks, or food) to see if you’re getting sodium through them. If not, you may want to consider adding an electrolyte fizz tab to your beverage (like Nuun tablets or SiS, for example) or choosing a higher sodium fuel source.
There you have it – 3 essential tips for running in hot weather! I hope this helps as you train throughout the summer. (PS – need some tips for running in cold weather? Check out this post!)
Share with me: Do you prefer hot weather or cold weather running? Any other tips you have for conquering the heat?
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A sweat test huh?!?! I have not heard of this, but I may use this is my workouts. Thanks for sharing!
No problem Rachel! I use it a lot with my endurance athletes to make sure they’re hydrating right.
You had a lot of interesting information in here that I did not know, like that it takes your body 2-4 to acclimate to hot temps. I am starting my half-marathon training now, so this is perfect timing!
So glad you found this helpful Kayla. I hope your half marathon training goes awesome! What race are you signed up for?
It has been tough going out there for me lately! I went back to using Gatorade and it does help me.
I taught a bunch of zumba kids classes a few years ago in the dead heat of summer. Even though it wasn’t really super intense, I came home with headaches unless I had a sports drink like Gatorade. I think the hydration + sodium can go a long way in the heat.
The timing of this post was perfect! I’ve really picked up the hobby of running lately and it’s been so hot. I can’t really tell you if I prefer hot or cold weather running just yet since I have yet to experience a cold Pacific Northwest winter.
That’s awesome! Stick with it, even if those hot days get to you. The spring/fall running is the best in my opinion 🙂
Great tips here! Pinning for reference as I get so many questions about this and salty sweaters. Can people buy sweat test equipment in the store? Is it accessible?
That’s a good question and I’m not actually sure Sarah. I usually just use the weight as a measure of the sweat test to see if hydration is right, and then if people complain of heavy salt sweating /cramps / headaches I’ll work with them on increasing sodium. But I’m not sure if there’s a way to actually test their sweat as to salt composition.
Awesome tips. I see so many people running here in FL in the heat and I always hope they are taking care of themselves.
I’ve ran in the Florida heat a few times on vacation and it is crazy!
great tips! i hate walking in the summer heat and move it inside to a treadmill. much prefer fall, winter, and spring outdoor workouts!
I think I like fall the best, especially in New England. I love the changing colors on the trees at that time of year; it makes for scenic runs 🙂
Awesome tips Chrissy. The heat I can do. It’s the humidity that gets me.
Oh yea, the humidity can make or break the run. If it’s hot and humid, it can get unbearable.
Run in the early morning or at night after sunset. Wear light colored clothing made of light material. Always wear a hat and sunglasses to protect your head and eyes from the sun. Don’t run a far distance from your home/car, in case you need to stop or take a water break (I do loops for my long runs, that always come back to my front porch where I lay out snacks, nuun and water).
Great tips 🙂 Looping around for water breaks is a great suggestion!! I also used to plan my long runs so that I’d pass a convenience store, that way if I needed extra sports drink I could stop and by some.
Great tips! I’m not usually a runner but summer always makes me want to be active outside so I’ve recently started running again. But it’s been so hot that I never actually go for my runs until just before the sun sets. Talk about late night runs.
I know, it’s tough this time of year. Could you run on a treadmill inside earlier in the day if you didn’t want to run outside so late? That’s what I do some days here 🙂
I’m sensitive to the heat (my fair skin doesn’t help), so I always try to get my outdoor workouts done in the mornings before it gets too hot.
Super smart Fiona. If you can avoid the hot weather and won’t be racing in it, it’s great to do the early morning/late evening runs.
Haha, avoiding it can be a great option too! If you know you’re not going to race in the heat, then I’m with ya – just run at a more comfortable time.