Describing individual variation in local sweating during exercise in a temperate environment

Abstract

It has been previously demonstrated that the individual variation in whole-body sweat rate is described by differences in each participant's heat balance status. It was hypothesized that the individual variation in local sweat rate of the forehead (LSR(head)) and forearm (LSR(arm)) would be similarly described using a whole-body heat balance approach, specifically the ratio of evaporation required for heat balance relative to the maximum evaporation possible (i.e. E (req):E (max)). Twelve males cycled at 60% [Formula: see text] for 60 min at 24.9 ± 0.5°C, 31 ± 14% relative humidity. Rectal (T (re)) and aural canal (T (au)) temperatures as well as mean skin temperature ([Formula: see text]), metabolic energy expenditure (M) and rate of external work (W) were measured throughout. In addition, whole-body sweat rate at steady state (WBSR(ss)) was estimated using the change in body mass over the last 15 min of exercise, with LSR(head) and LSR(arm) estimated using technical absorbent patches applied between the 50th and 55th minute. WBSR(ss) significantly correlated with M-W (r = 0.66, P = 0.021), E (req) (r = 0.69, P = 0.013) and E (req):E (max) (r = 0.87, P < 0.001); LSR(head) was significantly correlated with E (req):E (max) (r = 0.82, P = 0.001), but not M-W (r = 0.31, P = 0.328) or E (req) (r = 0.38, P = 0.227); and LSR(arm) significantly correlated with E (req) (r = 0.62, P = 0.031) and E (req):E (max) (r = 0.78, P = 0.003) but not M-W (r = 0.56, P = 0.059). None of WBSR(ss), LSR(head) or LSR(arm) significantly correlated with any variations in T (re), T (au) or [Formula: see text] (i.e. 0.8T (re) + 0.2[Formula: see text]). Secondary analyses also demonstrated that both LSR(head) (r = 0.79, P = 0.002) and LSR(arm) (r = 0.89, P < 0.001) correlated with WBSR(ss). In conclusion, the individual variation in WBSR(ss), LSR(head) and LSR(arm) is described by the ratio of E (req) relative to E (max).

Large differences in peak oxygen uptake do not independently alter changes in core temperature and sweating during exercise

“…Collectively, the data of the present study support the notion that studies wishing to primarily compare sweating responses between independent groups should administer exercise intensities that yield similar E req and E req /E max values (2,34,45) irrespective of %V O 2 peak . To achieve equal E req and E req /E max values between groups of different BSA, exercise must be administered to generate the same metabolic heat production per unit surface area (4,27).…”

“…It is very well established (2,21,34,45) that irrespective of core temperature, the rate of whole body and local sweating is determined by the rate of evaporation required for heat balance E req and the skin wettedness required for heat balance (i.e., E req /E max ). The present data clearly show that this relationship is not altered whatsoever by large differences in V O 2 peak .…”

Sweat-inducing physiological challenges do not result in acute changes in hair cortisol concentrations

“…The local sweat rate of the forehead was measured using the technical absorbent (TA) method (Havenith et al, 2008;Bain et al, 2011). Briefly, a TA pad (#2574, Laminated Airlaid, Technical Absorbents Ltd, Grimsby, UK) with a surface area of 6.25 cm 2 was prepared for each participant.…”

“…Afterwards, the TA pad (without frame) was put back in its container and weighed again. Sweat rate was calculated as the change in weight (pre-and post-application mass) divided by the surface area of the TA pad and the duration of application in units of mg per min per cm 2 (Bain et al, 2011).…”

Capacidad Del Método De Parches De Sudoración Para Detectar El Efecto De Un Antitranspirante.

“…Desde entonces se ha realizado un número limitado de estudios sobre la tasa de sudoración localizada (TSL) (Bain, Deren & Jay, 2011). Un método utilizado para recolectar el sudor de determinada zona corporal son los parches de sudor, los cuales eran empleados originalmente por las autoridades para la detección de drogas en el organismo (Phillips & McAllon, 2008), su uso fue tan eficaz para la recolección de sudor que se volvió un material indispensable en algunas áreas de termorregulación, particularmente en estudios relacionados con el deporte (Havenith, Fogarty, Bartlett, Smith & Ventenat, 2008;Morris, Cramer, Hodder, Havenith & Jay, 2013;Shirreffs, Aragón-Vargas, Chamorro, Maughan, Serratosa & Zachwieja, 2005).…”