Physiological and perceptual responses of wearing a dryrobe for rewarming after passive cold-water immersion in men

To investigate the physiological and perceptual responses to wearing a dryrobe for rewarming after passive cold-water immersion (CWI).

15 unhabituated healthy Caucasian men (age: 28.9 (5.4) years) attended the laboratory on three occasions and performed passive CWI (14°C) for 30 min followed by 15 min of rewarming wearing either a dryrobe, towel or foil blanket while positioned in front of fans replicating a 10 mph wind. Physiological (deep body temperature, skin temperature and heart rate) and perceptual (thermal sensation and thermal comfort) variables were measured.

At 15 min post-immersion, deep body temperature was higher in the dryrobe condition (mean: 37.09 (SD: 0.49)°C) compared with the foil blanket (36.98 (0.64)°C) and towel (36.99 (0.49)°C) (p<0.001). On average across the 15 min post-immersion period, the dryrobe increased skin temperature to the greatest degree (18.9 (1.0)°C, +2.4°C), compared with the foil blanket (18.1 (1.2)°C, +1.8°C, p=0.034) and the towel (16.6 (1.2)°C, +1.3°C, p<0.001). Average heart rate across the 15 min post-immersion period was lower when wearing the dryrobe (dryrobe: 74 (10) b.min^-1, foil blanket: 78 (6) b.min^-1 and towel: 82 (14) b.min^-1 (p=0.015). Thermal sensation and thermal comfort were higher at all post-immersion time points in the dryrobe compared with the foil blanket and towel.

During the rewarming period following CWI, physiological and perceptual responses are improved when wearing clothing that combines an insulative layer with a vapour barrier, such as the dryrobe compared with a towel or foil blanket. This might have future implications for safety recommendations during rewarming.