The 8-week protocol
Eight weeks, written down to the degree and the second.
The protocol starts around 12 °C for short, supervised exposures and progresses over eight weeks. Every temperature and duration is written into your program — nothing is improvised or pushed past your tolerance.
The shape of it
As the water gets colder, you stay in longer. The two curves cross around week four — that crossing is the whole program.
Water temperature 12 → 5 °c Max immersion 0:30 → 4:00 min
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Week
Week by week
Wk Water Immersion Monitored
1 12 °c 0:30 min Cold-shock response, heart rate
2 11 °c 1:00 min Heart rate, breathing control
3 10 °c 1:30 min Heart rate, blood pressure
4 9 °c 2:00 min HRV, perceived recovery
5 8 °c 2:30 min HRV, resting heart rate
6 7 °c 3:00 min HRV, recovery, adherence
7 6 °c 3:30 min Full panel review
8 5 °c 4:00 min Full panel + program report
On the deck
A trained supervisor stays on the deck for every immersion and watches your response. We end a session the moment your body says so — the written numbers are a ceiling, never a target.
