Human total, basal and activity energy expenditures are independent of ambient environmental temperature

Lower ambient temperature (T-a) requires greater energy expenditure to sustain body temperature. However, effects of T-a on human energetics may be buffered by environmental modification and behavioral compensation. We used the IAEA DLW database for adults in the USA (n = 3213) to determine the effect of T-a (-10 to +30 degrees C) on TEE, basal (BEE) and activity energy expenditure (AEE) and physical activity level (PAL). There were no significant relationships (p > 0.05) between maximum, minimum and average T-a and TEE, BEE, AEE and PAL. After adjustment for fat-free mass, fat mass and age, statistically significant (p < 0.01) relationships between TEE, BEE and T-a emerged in females but the effect sizes were not biologically meaningful. Temperatures inside buildings are regulated at 18-25 degrees C independent of latitude. Hence, adults in the US modify their environments to keep TEE constant across a wide range of external ambient temperatures.

Automated summary

The effects of ambient temperature on human energetics may be buffered by environmental modification and behavioral compensation. In the US, adults modify their environments to keep total energy expenditure constant.