Combined torso and foot heat exposure reduces acute ad libitum energy intake in young adults

This is the authors' abstract. We don't add key points for this paper.

Lowering body temperature with cooling vests has been shown to increase energy intake (EI), but it is unclear whether a heating strategy would have the opposite effect and modify EI. We examined the acute effects of combined torso and foot heat exposure via a hot vest and a warm foot bath on EI. Eight young females and eight young males performed two randomized and crossover trials, 28 d apart. Trials on female were conducted during the early follicular phases. In the control trial (CON), participants remained seated from 09:30 to 11:30. In the hot trial (HOT), they remained seated from 09:30 to 10:30, after which they wore a hot vest (~45°C) and took a foot bath (~43°C) from 10:30 to 11:30. From 11:40, participants were given up to an hour to consume a buffet meal. EI was calculated from the buffet meal. Tympanic and skin temperatures, appetite, and thermal sensation were assessed. Tympanic temperature, skin temperature and thermal sensations were higher in HOT than in CON during 10:30–11:30 (all p < 0.05). EI, food amount, hot foods, and hot beverage consumption were lower in HOT compared with CON (all p < 0.05). Subjective appetite was similar between the two trials. Linear mixed model revealed that lower EI trended to be linked to higher tympanic temperature (β = −6.060, p = 0.069). Combined torso and foot heat exposure decreased EI in young healthy adults, with tympanic temperature predicting this reduction and no changes in subjective appetite.