Breathwork

Controlled breathing protocols — box breathing, 4-7-8, Wim Hof, and CO2 tolerance — for stress, HRV, and alertness.

Evidence is mixed

Acute effects of controlled breathing on HRV and stress are robust across dozens of RCTs. Long-term cognitive and mood benefits are less well-characterised. Wim Hof protocol claims outrun the controlled evidence; box breathing and slow breathing at ~6 breaths/min have the strongest mechanistic and RCT support.

Evidence base

Min quality:

Loading papers…