The Cognitive and Physiological Effects of Heating the Torso of a Submerged Diver

Abstract

Seven U.S. Navy divers were submerged in 7.2 ºC water for a maximum of two hours wearing a semidry suit. In one of the conditions they were provided with external heating, and in the other they were unheated. In the heated condition, a total of 35 W was delivered to each of four heating pad (total area 2,477 cm 2 ) placed on the torso of the divers. Statistical analysis demonstrated that providing heating to the divers afforded no benefits in reducing the effects of cold water exposure on the skin temperature of the body extremities (fingers and toes) or in enhancing manual dexterity, grip strength, or cognitive performance when the effects of such heating were compared to those of the unheated condition. However, the participants reported that they would rather dive with the heating system than without it.