He is 61 years old and scruffily bearded, with a growly, booming voice that’s easily heard at a distance. “Oooh, look at all those fears!” Wim Hof says, reading the sign in mock terror. You Only Survive Few Minutes.” And if that isn’t enough of a deterrent: “Dangerous Currents.

For anyone unaware that it is ill-advised to jump in for a dip, a big red sign spells out the hazards: “No Swimming-Freezing Water. On the far side of the lagoon, a glacier called Vatnajökull hunkers like the beast that it is: a 3,100-square-mile ice cap that sprawls over southeast Iceland, dwarfing other European glaciers. The icebergs are dazzling white and pale gray and a light milky blue, and striped with volcanic ash the water is the color of dull metal. Slabs and hunks and blocks of ice the size of ships, houses, buses-they’re everywhere, crowded into the glacial lagoon. All rights reserved.The air is cold but the water is colder, its surface gridlocked with icebergs. They also suggest the compelling possibility that the WHM might allow practitioners to develop higher level of control over key components of the autonomous system, with implications for lifestyle interventions that might ameliorate multiple clinical syndromes.ĬNS thermoregulation Cold exposure FDG PET Functional MRI Hydroxyephedrine PET Periaqueductal gray Stress-induced analgesia Wim Hof method.Ĭopyright © 2018 Elsevier Inc. Our results provide compelling evidence for the primacy of the brain (CNS) rather than the body (peripheral mechanisms) in mediating the Iceman's responses to cold exposure. Finally, forceful respiration results in increased sympathetic innervation and glucose consumption in intercostal muscle, generating heat that dissipates to lung tissue and warms circulating blood in the pulmonary capillaries. However, the activation of brown adipose tissue (BAT) was unremarkable. In addition, the WHM also engages higher-order cortical areas (left anterior and right middle insula) that are uniquely associated with self-reflection, and which facilitate both internal focus and sustained attention in the presence of averse (e.g. fMRI analyses indicated that the WHM activates primary control centers for descending pain/cold stimuli modulation in the periaqueductal gray (PAG), possibly initiating a stress-induced analgesic response. This acquisition allowed us to determine changes in sympathetic innervation (HED) and glucose consumption (FDG) in muscle and fat tissues in the absence of the WHM. In addition, the Iceman also underwent a whole body PET/CT imaging session using the tracers C11-hydroxyephedrine (HED) and 18F-fluorodeoxyglucose (FDG) during both thermoneutral and prolonged mild cold conditions. fMRI was acquired in two separate sessions: in a typical (passive) state and following the practice of WHM. Thermoregulatory defense was evoked by subjecting the Iceman (and a cohort of typical controls) to a fMRI paradigm designed to generate periods of mild hypothermia interspersed by periods of return to basal core body temperature. To investigate this, we conducted multi-modal imaging assessments of the brain and the periphery using a combination of fMRI and PET/CT imaging. The relative contributions of the brain and the periphery that endow the Iceman with these capabilities is unknown. Here we present a case study of a 57-year old Dutch national, Wim Hof, the so-called 'Iceman', with the ability to withstand frequent prolonged periods of extreme cold exposure based on the practice of a self-developed technique involving a combination of forced breathing, cold exposure and meditation (collectively referred to as the Wim Hof Method, henceforth 'WHM'). There is however, anecdotal evidence of a unique set of individuals known for extreme cold tolerance. Autonomous mechanisms of thermoregulation are only weakly affected by top-down modulation, allowing only transient tolerance for extreme cold. The defense of body temperature against environmental thermal challenges is a core objective of homeostatic regulation governed by the autonomic nervous system.

Wim hof method overview