Side by side
| Chilled cold plunge | Ice bath | |
|---|---|---|
| Temperature | Set and held (often 3–15 °C) | Changes as the ice melts |
| Upfront cost | Higher (tub + chiller) | Low (any tub) |
| Running cost (≈ 380 L, indoors, daily use, our model) | ≈ 2 kWh a day with an insulated tub | ≈ 60 kg of ice to cool a fresh fill by 14 °C, then ≈ 6 kg a day (insulated tub) to 58 kg a day (stock tank) |
| Hygiene | Filtration, often ozone or UV | Water changed often |
| Effort | Low | Buying, carrying and adding ice |
Each kilogram of ice absorbs about 375 kJ while melting and warming to 10 °C, which is why ice adds up quickly in uninsulated tubs.
Getting started safely
Start with short immersions (30–60 seconds) at moderate temperatures, breathe slowly through the first cold shock, never plunge alone or after alcohol, and ask a doctor first if you have a heart condition.