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The list of things that are certain for a runner is not all that long. As Benjamin Franklin said, we have death and taxes. All year-long runners share another certainty, though—we spend a lot of time running in conditions that are crappy for optimal performance.
Coaches everywhere are currently hearing a tragic lament in training logs. “It was hot and miserable.” “I need to wake up at 4am to beat the heat.” “I am a bad heat runner.”
My answer to that is: no, no, and HECK TO THE NO. Everyone is affected by heat; it’s inevitable, and you need to embrace it. Because if you don’t make heat your friend, you are doomed to spend some of the most beautiful months each year getting intimate with misery. Plus, there’s a good chance your summer races will have some hot weather, so embrace the heat in advance. Otherwise, you’ll may find yourself compulsively checking the long-range forecast so often that you become an honorary Weather Channel meteorologist.
You can even settle for something like a high-school frenemy—something you’re friendly with even though it makes you suffer sometimes. Over time, you might find that the summer heat has some redeeming qualities. And it’s kinda nice when you really give it a chance. And maybe you could sit with at the cafeteria during lunch hour. And maybe you can study together. Does summer heat have a prom date?
How can you go from enemy to prom date? Here are four tips to change how you think about the heat and learn to savor the scorch.
Heat affects everyone
Heat reduces performance for all runners. Yes, performance impacts are greater in Sarasota than Seattle. But every runner is going through the same thing, some just have a better approach to handle it.
Work on setting up a framework for acceptance. Anticipate the heat and grow to love it. Remember that easy is not a pace, it’s an effort, so slow down as much as needed to keep it chill.
A 2012 article in the journal PLoS One found that heat was the biggest predictor of marathon performance across nearly two million race results, with some performance reductions of 10 percent on the hotter days. Dew point (a metric combining temperature and humidity) is particularly important. Even low dew points between 55 and 60 degrees can have a minor negative impact on performance. A 2016 review in the Journal of Applied Physiology goes over the mechanisms—higher skin and core temperatures (and associated bloodflow for cooling) reduce max oxygen uptake, increasing cardiovascular strain and desire to say “Screw this, I’m going to eat a McFlurry in the shade.”
We all know this intuitively. Hot days are slower; hot and humid days are slowest; hot and humid and sunny days are slowerest (this is when climbing any hill, no matter how slowly, feels like climbing Mount Everest). But just because you are going slower doesn’t mean it has to be less fun. Speed and enjoyment should be independent variables. Or they better be, otherwise, later on, Father Time is going to make sure you really don’t enjoy running as you age.
In the face of seasonal inevitability, you shouldn’t have to waste time each year on all five stages of summer grief: denial, anger, bargaining and depression do not have to be an annual ritual. Instead, work on setting up a framework for acceptance. Anticipate the heat and grow to love it (just like aging). Remember that easy is not a pace, it’s an effort, so slow down as much as needed to keep it chill. Do that, and summer can be a time of celebration of the running journey.
You get used to it
Thankfully, acceptance of heat doesn’t mean you have to accept that first hot-day feeling all summer. We all know what that feels like. About an hour into a run, it feels like a Herculean effort to go another mile and a Sisyphus-style task to try to go up the smallest hill. Your fingers tingle and your scalp pringles. No pace is slow enough, no Greek tragedy descriptive enough. That all gets back to the cardiovascular strain from running in the heat.
After a short period of acclimation, though, it gets better. One 2015 study in the Scandinavian Journal of Medicine and Science in Sports found that five training sessions in a 40-degrees Celsius environment reduced thermal and cardiovascular strain in cyclists. A 2018 review study in the journal Sports Medicine found that five or more days of heat training are enough to cause adaptations (and decay of heat adaptations happen more slowly, around 2.5 percent per day). One mechanism for the quick adaptation is blood plasma volume expansion, which reduces cardiovascular strain. A 2015 study in the European Journal of Applied Physiology found that just four sauna exposures of 30 minutes immediately after exercise can increase plasma volume by 17.8 percent.
Embrace the adaptation period, and you’ll feel better in the heat quickly. Constantly trying to avoid heat as if you’re playing a game of hot potato with the weather forecast, and you’ll never get over that first-day difficulty. Even after you adapt, you will be going a bit slower than in optimal conditions, so make sure you do some shorter, faster strides and intervals to keep your top-end speed (similar to how athletes should train at altitude).
How you perceive heat matters
How people perceive of their experience matters in almost every study. The placebo effect, for instance, has real physiological consequences. One extreme example of the placebo effect at work was published in 2007 in the General Hospital Psychiatry Journal. It involved a study participant taking what he thought were 29 anti-depressants, but were actually placebo pills. Even though the pills didn’t change his underlying physiology, ingestion led to severe low blood pressure that had to be stabilized with IV fluids. After he found out they were placebo, symptoms rapidly abated. The basic takeaway? While that case study is not directly analogous to running, it’s important to remember for all things that our psychology has power over physiological response.
In running, one somewhat bizarre 2015 study in the Scandinavian Journal of Medicine and Science in Sports found that performance improved significantly when athletes used a menthol mouth rinse during exercise. Meanwhile, performance did not improve when ingesting an ice slurry. Hypothetically, the ice should lower core temperature, while the mouth rinse only feels like it does. So perception of thermal sensation can matter as much as actual thermal response (in that study, at least). A 2016 review study in the journal Sports Medicine backed that up, finding that perceptual changes are important in heat adaptation.
So take control of your perception. Embrace warmer conditions, and your body could respond to the stress better. Be like Lebron in 2010—take your talents to the heat.
Heat makes you stronger and faster
Aside from simply enjoying running more, there’s another reason to make heat your friend—it can lead to big performance improvements, possibly even in cooler weather.
It all gets back to increased blood volume and reduced cardiovascular strain. Heat acclimation essentially gives you more blood to pump, and that theoretically should improve performance under all conditions. A 2014 article in Sports Medicine described these theoretical bases of performance improvements and a 2015 proposal article in the Journal of Physiology further articulated the hypothesis, but both noted the need to further study how heat acclimation impacts cool-weather performance. Since then, studies have been mixed, with some showing no performance increase in cool conditions (like this 2015 study on trained cyclists), but all showing performance improvements in the heat.
It’s a lot like altitude, which also increases training adaptations. People travel thousands of miles and spend thousands of dollars for altitude camps. So if you have a heat camp out your back door, consider yourself fortunate. Heat will make running a little bit less pleasant at first, but, make heat your friend, and you might find the key to psychological and physiological breakthroughs this summer.
—David Roche partners with runners of all abilities through his coaching service, Some Work, All Play