Three minutes at ten degrees

I avoided cold exposure for years because the idea sounded miserable. Then I read the Søberg lab paper on brown fat activation and decided to try it for 30 days. Three minutes, water as cold as my tap goes, end of every shower.

The first week was rough. Second week, easier. By day 20 it stopped being a willpower exercise. Now if I skip it the day feels off.

What is actually happening: cold exposure drives a large, sustained rise in dopamine that builds over the session and stays elevated for hours afterwards — without the crash you get from a stimulant. That is not a small effect. It also activates brown adipose tissue, which is linked to better glucose handling and resting metabolic rate. The Søberg work saw measurable changes after eight weeks of three‑minutes‑a‑day.

You do not need an ice bath or a fancy plunge. Cold tap water works. The temperature threshold for the response is somewhere around 14 °C, and most apartment taps in Germany run colder than that. Wim Hof has built an entire methodology around this, and Andrew Huberman has a free deliberate‑cold protocol summary on his site that breaks down the timing.

“The dopamine release from cold is more sustained than caffeine and produces zero crash.”

Recommended · 

Portable Cold Plunge Tub

Inflatable, 3-min setup. 4°C cold for 8 weeks → measurable brown-fat activation per Søberg lab.

~€199 Buy on Amazon →

Disclosure: Amazon affiliate link · We only recommend gear we actually use.

If you want to upgrade to a real plunge eventually, the portable inflatable tubs run around €200. Plunge and Ice Barrel are the two brands worth knowing. For a starting protocol though, your shower is enough.