Heat Adaptation for Spring Races

Originally posted by Chicory on April 4th, 2017 – one year ago today!

heat adaptationSpring weather is as erratic as Poppy’s two-year-old’s mood, yet that doesn’t stop us from signing up for races during months that aren’t sure if they’re happy (45° and cloudy), sad (35° and rainy), or having a meltdown (75° and sunny).

When you race in the late spring, you’re not heat-adapted like you might be for a fall race — unless you’ve been running on your treadmill in a sauna, that is.

So without going to that much of an extreme, how can you prepare for a spring race that might be warm, or even downright hot? I decided to talk to our resident racing in the heat expert, Poppy, to share her best tips for preparing for Mother Nature potentially throwing you a hot race day after a long season of cool or cold weather training!

Heat acclimation is something Poppy has done for several marathons under the guidance of her coach (and husband), Terry Shea. It’s a good thing, too, because she keeps finding herself racing in hot and humid conditions. Most recently, she ran the Houston Half (64° with 100% humidity) in January after the Rock ’n’ Roll Philadelphia Half in September (70s and humid).

Chicory: So what’s your background with heat acclimation training?

Poppy: I have done heat acclimation training a few times over the past ten or so years. It has been very helpful when I’ve raced in warm or hot conditions, but not necessarily as helpful in humid conditions, as evidenced by my last two half marathons. When I ran Grandma’s in 2015 I overdressed while it was 70-80° and super humid for my final two weeks of training and then on race weekend in Duluth it was in the 60s and dry; I was freezing whenever I was just sitting around. I also felt totally comfortable during the race (though to be fair, it was 60° and rainy), so that was a case where I really noticed the overdressing worked. I also did that for a warm Boston (2005) and a warm Chicago (2011) and never felt overheated or too hot while racing in the low 70s.

Chicory: What’s the strategy you use for acclimating?

Poppy: I basically overdress for the last two weeks leading up to the race. I ease into it and then add a garment each day. I definitely had a few runs going into the second week where I was wearing a hat and gloves when it was 50-60° out. I don’t even want to know what my neighbors think when I’m in overdressing/heat acclimation mode! I ran by the Bucknell XC women’s team back in September when I was getting ready for the Philly Half and I had on full winter gear while they sauntered by in their sport bras and shorts. Felt like an idiot.

Chicory: How do you decide which races to use this strategy for?

Poppy: My husband has me, and all his athletes, do this for pretty much any goal race that will be run with potentially warm weather. The goal is to feel comfortable on race day if the temperature is above what you’re used to. He recommends dressing as if it is 10-20° colder than it really is. For instance, if it is a day in the upper 50s, instead of going out in shorts and t-shirt, dress as if it is in the 40s and wear tights and a long sleeve.

Chicory: What about workouts? I hate doing speed work bundled up. In fact, if I can’t be in much more than shorts and a long sleeve, I’ll consider the treadmill instead.

Poppy: For workouts, I’d overdress for warm up and cool down and then strip down a bit for the workout. I think for a few marathons though, the very last workout, which is pretty light, like 3 x 1600 or 5 x 800 at MP, I might stay overdressed. It does suck trying to run fast while you are tapering and overdressed, but because it is a shorter workout and in theory should be easy (never feels it), overdressing doesn’t seem like much of a big deal.

Chicory: Where do you draw the line?

heat trainingPoppy: Coach Terry suggests only overdressing into the 70s. If it happens to reach the 80° mark, there’s no need to overdress on top of that!

Chicory: How much of this do you think is physical versus mental? Not saying that it matters. I know when it gets hot, and especially when it is sunny, my mental reaction is that I’m literally boiling, which isn’t exactly true.

Poppy: I think it helps on both accounts. I will say though that I know it’s working when I’m sitting around in 70° weather and need to put on a hoodie to keep my butt from freezing. And also, the warm temperatures feel comfortable racing, but I still need to figure out how to acclimate for hard racing in humidity!


Looking for other tips to race in hotter weather than you have to train in? Cilantro offers up her tried and tested advice as well!

How do you train for hot races?

Sal is a 4 year old 77 hour trail marathoner looking to whittle a few minutes off next time. Being a gastropod, Sal is neither male nor female but will accept either set of pronouns. Sal's spirit animal is the cheetah and Sal's mantra is, "What's slow to some is fast for others." Sal writes about Salty Running news.

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  1. So much great stuff here! I’m in Canada, and we often face the challenges of training through cold winters and then getting hit with a hot day for spring races (Boston 2017, I’m looking at you!). It’s hard to overdress when it’s minus 30! I do find some treadmill sessions and indoor track sessions help at least a bit!

  2. This is actually quite comforting. As someone whose last two marathons have been brutally hot, I did find the humidity of Florida harder to deal with than the heat of Vermont, though both races were hot and humid. I agree with Jesse – when outside temps are super duper cold (hers are worse than mine even!), it’s really hard to overdress. While training in New England in January, I was already wearing everything I own just to be comfortable running outside. I have a friend who did train in a hot disgusting gym in the far north – she fared much better than I did in the Florida heat in February. I guess that strategy works, but I am not sure it is worth it, at least maybe not to me.