← Glow: The New Science of Living Longer

Chapter 8: Sweat, Shiver, Repeat

Chapter 8 of Glow: The New Science of Living Longer

Glow: The New Science of Living Longer cover

Let’s talk about one of the most powerful — and ancient — ways to heal your body:

🔥 Heat + ❄️ Cold = ⚡ Reset

This is thermal cycling. Or as I like to call it: “The ancestral reboot button.”

Sauna, steam room, cold shower, ice bath — whatever you have access to, the benefits are real, fast, and kind of magical.


The Oldest Biohack in the World

Before there were doctors, there were sweat lodges. Before there were pills, there were hot springs and ice lakes.

And now? Science is finally catching up.

A major study out of Finland (the land of saunas and long life) found:

Your ancestors knew. Your mitochondria still remember.


Why It Works

Heat activates:

Cold activates:

Together, they reset your body like a power cycle on a glitchy computer.


How to Do It (Without Crying)

Step 1: Find your version of heat

Step 2: Get warm for 10–20 minutes

Step 3: Switch to cold for 1–2 minutes

Step 4: Repeat if desired. Step 5: Rest. Hydrate. Glow.


Do This 2–4 Times a Week

Even once a week makes a difference.

Don’t overthink it. Just rotate your temperature. Let your cells throw a little party.


Bonus Ritual Tips


TL;DR

Sauna and cold are not extremes. They’re rhythms.

You sweat. You shiver. You remember you’re alive.

And your cells get to say: “Thank you.”


“I enter the fire. I greet the ice. I emerge glowing and clear.”

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