The Wim Hof Method, a self-administered practice pairing fast breathing and breath-holds with cold exposure and focus, is sought for stress resilience. Trained people can trigger an adrenaline surge that dampens inflammatory reactions to a laboratory toxin; real-world relevance is unknown. For mood, sleep, heart health and performance, it did no better than slow breathing, meditation or placebo. Fainting during breath-holds can be fatal in or near water. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Resting blood pressure | No established target; track change from own baseline | Safety check: hypertension changes suitability of cold immersion |
| Resting electrocardiogram | No established target; review for arrhythmia or long-QT pattern | Safety check: abnormal rhythm stops cold-water submersion |
| Fasting glucose | 3.9–5.5 mmol/L (70–99 mg/dL) | Expected to change: fell with the full method in one trial |
| Erythrocyte sedimentation rate (inflammatory arthritis only) | 0–15 mm/h men, 0–20 mm/h women under 50 | Expected to change: fell in axial spondyloarthritis |
Cadence: Baseline before starting (electrocardiogram for people over 40 or with cardiac risk factors); blood pressure and symptom ratings at 4 and 12 weeks, then every 6–12 months; fasting glucose and inflammatory markers at 12 weeks, then every 6–12 months; electrocardiogram if palpitations, fainting or chest discomfort occur during cold exposure.