Your Body was Built for Heat. Start Using It.

The new science of why getting in the summer heat can boost your health, fitness, and even improve mental health.

Most people will stay indoors when it’s hot this summer—continuing to live, work, and exercise at 72 degrees.

But when we never get hot, we lose something fundamental.

Humans are unique among other mammals in that we can thrive and endure in the heat. We sweat, we’re mostly hairless, and we stand upright so the sun hits less of us. The heat shaped us into who we are, and it’s still good for us today.

I brought on two guests to discuss the power of the heat.

First, I talked to Ashley Paulson. She holds the women’s course record at Badwater 135. It’s the hardest, hottest ultramarathon on Earth, held in Death Valley in July, where temperatures range from 115F to 130F. Also: Ashley didn’t start competing until her fourth kid. She’s now a grandmother setting world records.

Ashley will tell us what running through hell for 21-plus hours feels like, how she trained for the heat, why you’ve got more in the tank no matter your age, and what you can learn from the world’s hardest and hottest foot race.

Then I talked to Bill Gifford. He’s a veteran health journalist and the author of Hotwired: How the Hidden Power of Heat Makes Us Stronger.

Bill will explain the science of the heat and how to use it: what happens to your body in the heat, the heart and brain health benefits of the heat, why heat functions like a multiplier for your workouts, and his honest take on where the evidence on heat is solid versus where the internet has overstated it.

Watch the episode

Listen to the episode

• This link opens the episode in your podcast player of choice.

Show notes

• Ashley’s Instagram.

• Badwater 135 Race.

• Bill’s Book: Hotwired: How the Hidden Power of Heat Makes Us Stronger

My Biggest Takeaways From the Episode

As a reminder, this new section is for Members only. Below are 8 of the highest-impact, most actionable takeaways from the episode, including:

• How to reprogram your sweat rate and cardiovascular efficiency in under two weeks.

• The core-temperature target and timeline scientists used to trigger a lasting 40% drop in depressive symptoms.

• What running 135 miles through Death Valley in 120-degree can teach us about pacing, fueling, and knowing your edge.