Altered Sympathoadrenal Activity Following Cold-Water Diving.

Introduction: Little data exist on the effect of extremely cold-water diving on thermo-metabolic hormone secretion. Moreover, the impact of repetitive dives on the stress response is unknown. The purpose of this study was to determine the effects of two daily bouts of cold-water diving on the hormonal and metabolic profile of elite military personnel and to measure the stress response.

Haemoconcentration, not decreased blood temperature, increases blood viscosity during cold water immersion.

Introduction: Prolonged cold-water immersion (CWI) has the potential to cause significant hypothermia and haemoconcentration; both of which have previously been shown to independently increase blood viscosity in vitro. The purpose of this study was to determine the effect of CWI on blood viscosity and examine the relative contribution of decreased blood temperature and haemoconcentration.

Methods: Ten healthy volunteers were immersed to mid-sternum in 10°C water for 90 minutes.

Cold Acclimation Does Not Alter Physiological or Perceptual Responses During Subsequent Exercise in the Heat.

Introduction: Warfighters often train and conduct operations in cold environments. Specifically, military trainees and divers that are repeatedly exposed to cold water may experience inadvertent cold acclimatization, which results in body heat retention. These same warfighters can quickly switch between environments (cold to hot or hot to cold) given the nature of their work.