Skin gradient of body temperature related to non-shivering thermogenesis 3 in humans at a lowered ambient temperature

We addressed the effect of lowered ambient temperatures i.e. 22 degreesC (72 degreesF) versus 27 degreesC (81 degreesF) in 8 women and 16 degreesC (61 degreesF) versus 22 degreesC (72 degreesF) in 9 men as part of a 24h non-shivering thermogenesis (NST3) measured in it respiration chamber. We defined this new concept, NST3 as total energy expenditure -(sleeping metabolic rate + diet-induced energy expenditure + activity related energy expenditure). This was 248 +/- 208 kJ/d at 22 degreesC and 714 + 505 kJ/d at 16 degreesC, and was related to the core-skin body temperature gradient (r = -0.95, p <0.001 and r = -0.7; p <0.05) thus limiting the increase in this gradient at a lower ambient temperature.