Tips for Running in the Heat & Humidity

Regardless of the date, or position of the moon, it’s summer here in Chicago.  And most days it’s not just hot, it’s humid baby.

Please do not mistake this as me complaining about the heat, after the winter we had, I say: “humidity, I welcome thee”.


However, as a runner humidity and heat are completely different animals when I’m running, in fact I’m sure it’s safe to say that for most runners.  Running in dry heat versus heat with humidity are two different types of hell.

Running on an 80 degree day with < 50% humidity, feels like you’re running on a really hot 80 degree weather day.  Once the humidity tips 70%, that 80 degree day then feels like a 95-100 degree day.  The issue of humidity come into play because that sweat our body makes to try to cool us down when we are exerting ourselves- and that sweat under normal conditions gets to our skin and is evaporated – so how we keep ourselves cool…

Hence, why if you’re like me when you’re done with a long run, you have little salt granules all over your face, but for the time being your face is dry.


When it’s humid, that “surface sweat” cannot be evaporated – so that nice cooling system is impeded, and we stay hotter.

So here are my key tips for dealing with humidity:

1) Slow Down

Embracing an adjustment in pace is difficult, but it is important.  Don’t expect to continue to clock 8 minute miles when humidity is surging.  Just brace yourself to run at a slower pace.

Here is a neat-o calculator on how to adjust your pace.

For me personally, I just plan to be “slower” If it’s a tempo run, I’ll give myself like an extra 15-30 second lee-way on what my ppm should be.  If it’s an easy run, I just don’t pay attention to my pace.  Track work- I’ll back off my pace a little bit too, if it’s a long run, again, I’ll anticipate an added 15-30 seconds per mile.

Everyone has their own system from what I understand, but definitely: DO NOT beat yourself up about not being able to maintain your “normal” pace.

2) Dri-Fit Clothes – all the way

I cringe when I see people on the trail when it’s humid, and I see their COTTON shirts just soaked.  That can’t feel good, it can’t.  I’m not saying that if you opt for “Dri-Fit” it will feel good – but it will feel better than that!

At least that material will wick away some of the excess sweat – it won’t resolve the problem, but it will help a tiny bit

3) Hydrate hydrate hydrate

On long run days, hot days, and humid days start hydrating prior to your run, so that the water has time to hydrate you all nice like.

On these hot and humid days hydrate definitely before, and definitely after.  Hydrating during the run depends on the distance/duration of the run.

If you’re running over 4 miles – take a water bottle with you.  Less than – likely safe to leave it at home.

This little guy is perfect to break out for runs once the weather heats up.  Due to its small size - it may not be ideal for longer runs
This little guy is perfect to break out for runs once the weather heats up. Due to its small size – it may not be ideal for longer runs

Also do NOT wait until you’re thirsty to drink.  I am guilty of this during humid half marathons… and I have suffered the consequences so dearly.

Last August in the Mag Mile Women’s Half, I remembered thinking I was super invincible for the first 4-6 miles.  I forget what mile it was, but there was a point where I just became so thirsty, and that’s when I realized I hadn’t taken a single pull off my water bottle…. This then resulted in drinking copious amounts of water, which did nothing but upset my stomach.

I ultimately threw up, and had to stop at a porta…

I finished, but it was an ugly finish.

Don’t wait until you’re thirsty to start hydrating!

4) Listen to your body

Some of us just respond differently to running in the heat and humidity.

If you become nauseated, woozy, dizzy, confused, muscle cramping, excessive sweating (I’m not sure how you distinguish heavy sweating) – STOP.  These may be signs of heat exhaustion.  So seriously, stop.

If you feel even minor versions of these symptoms post run, the best thing to do is get cooled down.  Put on clean dry clothes, start drinking cold water, basically get your body cool, and rehydrate.

Heat exhaustion can progress into heat stroke, if it progresses, so don’t let these symptoms progress.

5) Customize your nutrition

Even everyone’s sweat is different!  Some (me!) are salty sweaters.  For people who are, and do not take in enough electrolytes on long runs -this can impede performance lead to cramping, etc.


I am a fan of Nuun Electrolyte tabs – I use these both when it’s hot, and when it’s not.  I also like mixing them with La Croix when I’m done with a long run to make a little recovery “mock tail” (my personal favorite is Watermelon Nuun + Lime La Croix).

Additionally our bodies are going to be exerting more when it’s humid – even moreso diverting blood flow from non-essential areas (stomach) to more essential areas (legs, arms etc).  This is something that already happens that can make pre- and mid- race fueling so tricky, because, when there isn’t blood readily getting to your gut – that my friends slows down digestion – that can lead to feelings of nausea, reflux, discomfort, etc.

Which if you’re puking – not ideal for a hot, humid day, and your general hydration status.

6) Body glide

I mean this should be in your arsenal anyways.  For both men and women.

body glide

I don’t know how people run in hot weather without body glide.

7) Change your route

If you have the option, change up your route to one that’s shaded, if your normal route allows the sun beating down on you.  Again, considering the heat index, and how necessary it is to do your run, possibly consider the dread-mill.

8) Sunscreen People

Isn’t it amazing how (maybe moreso for girls) how when you’re 18 sunscreen is not even thinking about “bring on the tan”.  But as I’ve entered my 20’s, anytime I’m out in the sun for anything longer than just a quick tempo- that SPF hits my face (even for tempos – I’ll use a moisturizer after I wash my face that has like SPF 15-20 in it)…

a) I don’t want premature wrinkles

b) I don’t want skin cancer

This has nothing to do with humidity.

9) Consider changing the time of the run…

The exception to this rule is if you’re training for a race that you know will be in a hot/humid climate- if that’s the case train in the conditions you need to be prepped for.IMG_4019

This is something that can be very tempting to do over the summer in Chicago.  The Chicago Marathon is every October.  However, Chicago can actually be quite warm still in October.  So it is prudent to gut it out on some hot days, as it is fairly likely it could be pretty hot on race day

10) Buddy Up

So you decide not to opt for the dreadmill?  Opt for a buddy, this is good for the both of you.  Talking during a workout is another good way to gauge your effort.  Even if you’re both seasoned runners – if conversation get’s difficult it means it’s time to slow down the pace.


It’s also preferable if one of you is a good influence…. and serves as the reminder to stop and get water, and such things.

Full disclosure – on my long run this weekend I did not take any of my own advice…. It was an awful run.

home alone

That is literally what I said to myself when I ran the miles out, and realized how humid it was, and how incredibly thirsty I was…..

So please take my advice, because I have ran smart, and ran like an idiot.  I always feel better after I run smart.


  1. Thank you for the link to that calculator! Did a 10k tempo run in 80 degree heat this week and it was a fun preview of what’s to come with marathon training this summer! That calculator will come in super-handy!

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