Wim Hof method

The Wim Hof method combines cyclic hyperventilation-style breathing, breath holds, and gradual cold exposure, popularised by Dutch athlete Wim Hof. Small studies report transient effects on sympathetic activation, catecholamine release, and short-term immune markers after lipopolysaccharide challenge. Long-term and clinical benefits, including for chronic disease or longevity, remain unproven, and the breath-hold component carries risks of fainting, especially in or near water.