Lowering Your Core Body Temperature

August 15, 2013

In 5 weeks, a wonderful thing will happen to all of us who run. We will officially have survived another hot summer of training. Hallelujah! The first day of fall is within sight. But before we start brushing the dust bunnies off our running tights and arm warmers, many of us still have 35+ more days of heat and humidity to conquer.

To beat the remaining summer heat, an important strategy to focus on is lowering your core body temperature. When we’re exposed to heat during physical activity and vigorous exercise, our core temperature (which averages about 98.6 degrees at rest) rises. Our body is designed to cool itself off by sweating. But for people training for half marathons, marathons and long distance triathlons, sweat alone is often not enough to cool us down. Becoming overheated can lead to exhaustion, dizziness, nausea, fatigue and even heat stroke. And we all know it can cause serious mental frustration and diminished confidence due to one too many painful or lethargic runs after another.

Luckily, there are some proactive steps we can take to make the heat a little more bearable. Although our bodies should be fairly acclimated to the summer heat by this point in the season, lowering your core body temperature can help make those hot runs a little cooler. Today, I’m sharing my 8 tips for lowering your core body temperature during summer workouts.

8 Tips for Lowering Your Core Body Temperature from runladylike.com

1. Hydrate. Then hydrate some more! One of the most obvious strategies for lowering our core body temperature is to drink water. When exercising in the heat, our bodies lose water. When we lose too much, our internal cooling systems stop working. During exercise, a good rule of thumb is to drink several ounces of water or sports drink every 15 to 20 minutes, or about 13 to 27 ounces per hour of exercise. Be careful not to over-hydrate and flush electrolytes out of your system. But hydrating doesn’t just begin during your first mile. It should be happening daily, especially in the days leading up to a long run or race. It’s also critical to rehydrate after runs to replace the water your body has lost.

2. Get Naked. Ok, well maybe not naked, but try to wear as few clothes as possible. The more layers or thicker materials you have on your body, the hotter you’ll be and the more chafed you’re likely to get. Stay cool by wearing moisture wicking clothes that are light weight and breathable. Ladies, consider wearing just a sports bra, a dry-fit mesh tank and/or tanks that have a built-in shelf bra to reduce one extra layer. Forget the costumes and anything that will heat you up on race day too.

3. Chill out before your run. Eat and drink cold things that will lower your core body temperature before you hit the pavement or trail. Consider making a pre-race/run slushy with your water or sports drink in the blender with ice. If you eat a banana before you run, consider eating a frozen one. The longer it takes for you to heat up on your run, the slower your body temperature will rise.

4. Freeze your water bottles. The night before a long run or race, freeze the water bottles you’ll be carrying with you (or you’ll be getting along the route) so they will stay colder longer. I can typically keep frozen ice in my bottle for about 3 miles before it melts; however, the water stays cold through mile 10 or so. Drinking cold water as opposed to lukewarm water can help cool you down. This also works on the bike.

5. Ice, Ice, Baby! Don’t underestimate the power of ice in helping you conquer a hot run. Consider putting ice along your running route to dump into your clothes mid-run. I like to put ice in plastic baggies and then put one in my sports bra while I’m running until it melts. By having it in the bag, it won’t soak your clothes (if you aren’t already soaked in sweat), but a handful straight up works too. I’m notorious for reaching into the big Gatorade jugs my running group puts on long run routes to scoop ice out to put into my top. Consider putting ice in your shorts and in your hat if you wear one, too. The groin and armpits are said to be key areas where body temperature can be controlled. Can’t find ice? Pour cold water over your head and neck to cool you off.

8 Tips for Lowering your core body temperature from runladylike.com
Photo source: heidiklum.aol.com

6. Slow down. I know, I know. This is the last thing you want to hear, but slowing down can help you regulate your body temperature and breathing. For every degree over 65 degrees Fahrenheit, plan to slow your pace by 2 seconds per mile. Read more about adjusting your goals for hot weather running here.

7. Strategically select where you run and when. When possible, run in the early morning hours, which is the coolest time of the day. Try to select routes that have adequate shade, such as tree-lined paths. Consider running your speed work or tempo runs on the treadmill if the heat is really blazing.

8. InVEST in some cool gear. If you want to take your body temperature cooling to the next level, consider investing (no pun intended) in a cooling vest. There are a variety of brands out there that can be put in the freezer overnight and will help you stay cool for 30 minutes to 3 hours on your run (there are even fancier, battery-operated versions that will go longer). Various levels of sophistication and effectiveness are available at different price points. I’ve never used a cooling vest, but they’ve always intrigued me. Other gear that can help include a visor to shade your face/eyes and sunglasses. And of course, don’t forget the sunscreen.

How do you stay cool on your summer runs? Are there any other tips you would add to this list for lowering your core body temperature? If you’ve ever used a cooling vest, tell me about it!


Alyssa @ See This Girl Run

My strategy is basically go in the early morning hours before the sun gets too hot and take water with me! On one particularly bad run, I got my hat soaking wet and that really did help me feel so much better. But I try to avoid the heat if possible.

Rachel @ Health My Lifestyle

This may be a dumb question but when carrying a water bottle while running, do you hold it in your hold? Do you have a pack or belt for it? I want to do longer runs but I’m not sure how to transport a water bottle with me.


Hi Rachel! There are a variety of options out there, but I use a Nathan Handheld Water Bottle. Essentially, it slides onto your hand so you don’t have to grip your bottle and also includes a pocket for gels, phone, etc. it takes a few runs to get used to but I love it. Amphipod is another brand that has similar products. For me, a fuel belt is just too bulky and uncomfortable. I carry my Nathan Handheld on all runs longer than an hour, including races. Good luck!


ALL of those notes are awesome, and I know for sure that in Florida I can’t afford to speed up and then tucker our from dehydration – moderation and listening to my body has been key!

Lisa @ RunWiki

Great tips Jes! All of these things help when the heat is on! I can’t wait to meet you, message me your cell so we connect. Love you beautiful girl!! xoxo


These are awesome tips, hun! This is the first year i’ve really trained through the summer for fall races, and it has been a huge learning time for me to say the least ha. I always carry a water bottle, run where i can refill it at water fountains, run along rivers/shade/in the morning before work, and go a lot slower than I’m used to. That last one was the hardest to learn, but it helped a lot and i hope it pays off with some speedy fall races this year 🙂


Thank you for these great tips !
I sweat so much in the Florida heat, I worry a lot about dehydration. Im heading out to get the handheld water bottle you mentioned.

Jenn @ runnderlust

I read in Runner’s World that drinking cold water before your run helps keep you from fatiguing an extended 20 minutes because less energy is wasted from cooling your body temp—another great reason for hydrating!


Great tips! I’m always so hot but drinking ice water and munching on ice really helps!

Ali K. @ Hit the Ground Running

I’m so jealous of my friends in other states enjoying 60s in the mornings right now. It’s still 90 and crazy-humid here. Thanks for the tips!

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Jojo @ RunFastEatLots

Great tips! I wake up before the sun rises so I can run during the coolest parts of the day. I also try to run in the shade as much as possible. It really makes a difference!

On days that are so hot that I don’t feel like running, I crosstrain on my bike. The wind makes the heat a lot more bearable.

Fahim Bisswash

Sometimes I feel excessive temperature problem all over my body mostly in Summer season. When I face this problem I usually drink more n more water. Sometimes I drink cool watermelon juice or Lemon juice. This is very effective for me.