Warum 4 °C die ideale Temperatur für dein Eisbad ist

Why 4 °C is the ideal temperature for your ice bath

The ideal temperature for an ice bath – and what your body really experiences.

Introduction

Not all cold is the same.
There is not just a temperature difference between a cold shower, a 15-degree plunge pool, and a real ice bath – there is a completely different physiological state.

Many experts refer to 4 °C as the “sweet spot” – the point at which the body is maximally challenged but not overwhelmed.

But why exactly this number? And what happens in the body when it dives to this depth?

What happens in the body at 4 °C?

When immersed in 4°C cold water, your body reacts reflexively:

  • Blood vessels narrow (vasoconstriction) – the body protects its organs

  • Adrenaline & noradrenaline increase significantly – focus, clarity, energy

  • Heart rate increases, circulation is stimulated

  • Breathing becomes faster, often in bursts

  • After a few seconds, parasympathetic counter-regulation begins

The crucial point: This temperature is sufficient to effectively provoke all these reactions – without taking any unnecessary risks.

Scientifically speaking

Studies show:

  • Cold receptors in the skin are fully activated at temperatures below 10 °C

  • 4 °C is effective enough to trigger the desired hormone boost (adrenaline, endorphins, dopamine)

  • At the same time, the temperature remains within a safe range for well-prepared, healthy people

An ice bath at 4 °C is not a test of courage – but a precise, measurable stimulus for the autonomic nervous system.

Why not colder?

Water below 4°C not only feels colder – it is significantly harder to control.
The risk of hyperventilation, circulatory overload and muscle tension increases.
In addition, the time you can safely spend in the water is reduced.

Extreme cold ≠ better effect.
Regularity, control and breathing are more powerful than any piece of ice.

Why not warmer?

From about 8–10 °C the effect begins to diminish:

  • The body takes longer to switch to the sympathetic state

  • The dopamine response is significantly lower

  • The anti-inflammatory effect is less pronounced

In short: colder has a shorter effect – but more intense.

4 °C as ritual temperature

For us, 4 °C is not a coincidence – but a conscious decision:
A point between challenge and stability.
Between clarity and security.

This temperature:

  • Excites you – but doesn’t overwhelm you

  • Is reproducible & adjustable

  • Is ideal for daily rituals

4°C is no limit. It's an invitation to feel yourself—real, awake, present.

Further recommended:

  • “Breathing Technique & Ice Bathing”

  • “Rituals for Regeneration”

  • “Cold vs. Sauna”

Back to blog
1 3