Wim Hof (; born 20 April 1959), also known as The Iceman, is a Dutch motivational speaker and extreme athlete noted for his ability to withstand low temperatures. He previously held a Guinness World Record for swimming under ice and prolonged full-body contact with ice, and holds a record for a barefoot half marathon on ice and snow. He attributes these feats to his Wim Hof Method (WHM), a combination of frequent cold exposure, breathing techniques and meditation. Hof has been the subject of several medical assessments and The New York Times bestselling book What Doesn't Kill Us written by investigative journalist Scott Carney. Personal life Wim Hof was born on April 20 1959 in Sittard, Limburg, Netherlands. He was one of nine children. Hof met his first wife Marivelle-Maria, also called “Olaya Rosino Fernandez” (born in 1960, from Basque Country, Spain) in the Vondelpark in Amsterdam in the garden of roses. She died by suicide in 1995 by jumping from an eight-story building. She was diagnosed with schizophrenia. Wim Hof’s first relevant experiences with the cold go back to when he was 17: he felt a sudden urge to jump into the freezing cold water of the Beatrixpark canal. The first relevant scientific investigation began in 2011 at Radboud University. On 19 April 2011, the results of this study were broadcast on Dutch national television. Wim Hof Method Hof markets a regimen called the Wim Hof Method (WHM), which involves willpower, exposure to cold water, and breathing techniques. Hof states that his method can reduce symptoms of several diseases including: rheumatoid arthritis, multiple sclerosis , corona virus and Parkinson's disease. However, while hyperventilation might temporarily reduce inflammatory response to an injection of endotoxins, Hof's claims have not been scientifically proven. Wouter van Marken Lichtenbelt, one of the scientists who studied Hof, said: "[Hof's] scientific vocabulary is galimatias. With conviction, he mixes in a non-sensical way scientific terms as irrefutable evidence." However, Van Marken Lichtenbelt goes on to say: "When practicing the Wim Hof Method with a good dose of common sense (for instance, not hyperventilating before submerging in water) and without excessive expectations: it doesn't hurt to try." Studies on Hof individually In 2012, a case study led by a group of researchers in The Netherlands and published by the journal Psychosomatic Medicine titled The Influence of Concentration/meditation on Autonomic Nervous System Activity and the Innate Immune Response, found