Safety & Contraindications

Shallow water blackout

Also known as: Hypoxic blackout

German: Flachwasser-Blackout, Hypoxischer Blackout

A sudden loss of consciousness underwater caused by low oxygen after a breath hold, often following deliberate over-breathing. Over-breathing lowers CO₂ and can weaken the urge to breathe, so the usual warning signal may be missing and a person can black out without feeling distress. It is a main reason why breath holds and intensive breathing are never practised in water, not even in a shallow pool or when swimming alone.

Breathwork contraindications →