This study explored whether anthropometric measures influence magnitude of skin cooling following exposure to whole body cryotherapy (WBC). Height, weight, body fat percentage, and lean mass were measured in 18 male and 14 female participants. Body surface area, body surface area to mass ratio, body mass index, fat-free mass index, and fat mass index were calculated. Thermal images were captured before and after WBC (−60°C for 30 seconds, −110°C for 2 minutes). Skin temperature was measured at the chest, arm, thigh, and calf. Mean skin temperature before and after WBC and change in mean skin temperature (ΔT sk) were calculated. ΔT sk was significantly greater in females (12.07 ± 1.55°C) than males (10.12 ± 1.86°C; t(30) = −3.09, P = .004). A significant relationship was observed between body fat percentage and ΔT sk in the combined dataset (P = .002, r = .516) and between fat-free mass index and ΔT sk in males (P = .005, r = .622). No other significant associations were found. Skin response of individuals to WBC appears to depend upon anthropometric variables and sex, with individuals with a higher adiposity cooling more than thinner individuals. Effects of sex and anthompometrics should be considered when designing WBC research or treatment protocols.

Cycling capacity in the heat improved when participants used a commercially available cooling vest, but we observed no benefit from wearing a commercially available CC. The vest and the collar did not alter the heart rate, rectal temperature, skin temperature, or sweat-loss responses to the cycling bout.

Individualising the exposure of −110°C whole body cryotherapy: the effects of sex and body composition. Journal of Thermal Biology. 65, pp. 4147. 03064565. It is advisable to refer to the publisher's version if you intend to cite from this work. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractThe purpose of this study was to investigate the effects of whole body cryotherapy (WBC) on a range of thermoregulatory measures. We also sought to examine the influence of sex and body composition.A convenience sample of 18 healthy participants (10 males and 8 females) (27±6 yrs) volunteered for this study. Temperature (core, tympanic, skin and mean body), heart rate, blood pressure, and thermal comfort and sensation were recorded pre-and post-(immediately and every 5 min until 35 min post) exposure to a single bout of WBC (30s at -60°C, 150s at 110°C). Anthropometric data (height, weight, body surface area, body mass index, fat mass and fat free mass) were also recorded. No significant differences in temperature (core, tympanic, skin and mean body), heart rate, blood pressure, or thermal comfort / sensation were observed between male and females at baseline.Immediately post WBC mean body (male: 31.9 ± 0.8°C; female: 31.0 ± 0.9°C; ∆ mean body temperature: 0.9 ± 0.1°C; P ≤ 0.05, d = 0.64) and mean skin (male: 22.1 ± 2.2°C; female: 19.6 ± 2.8°C; ∆ mean skin temperature: -2.5 ± 0.6°C; d = 0.99, P ≤ 0.05) temperature was significantly different between sexes. Sex differences were also observed in regional skin temperature (male thigh, 20.8 ± 1.1°C; female thigh, 16.7 ± 1.1°C, ∆ mean thigh skin temperature: -4.1°C; d = 3.72; male calf, 20.5 ± 1.1°C; female calf, 18.2 ± 1°C, ∆ mean calf skin temperature: -2.3 ± 0.1°C; d = 3.61; male arm, 21.7 ± 1°C; female arm, 19 ± 0.4°C, ∆ mean arm skin temperature: -2.7 ± 0.3°C; d = 3.54; P ≤ 0.05). Mean arterial pressure was significantly different over time (P ≤ 0.001) and between sexes (male 0 mins: 94 ± 10mmHg; female 0 mins: 85 ± 7mmHg; male 35 mins: 88 ± 7mmHg; female 35 mins: 80 ± 6mmHg; P ≤ 0.05). Combined data set indicated a strong negative relationship between skin temperature and body fat percentage 35 minutes' post WBC (r = -0.749, P ≤ 0.001) and for core temperature and body mass index in males only (r = 0.726, P ≤ 0.05) immediately after WBC. There were no significant differences between sexes in any other variables (heart rate, tympanic and perceptual variables). We observed sex differences in mean skin and mean body temperature following exposure to whole body cryotherapy. In an attempt to optimise treatment, these differences should be tak...

The aim of this study was to investigate how body thermal resistance between sexes evolves over time in the recovery period after a WBC session and to show how this parameter should be considered as a key parameter in WBC protocols. Eighteen healthy participants volunteered for the study (10 males and 8 females). Temperature (core and skin) were recorded pre- and post (immediately and every 5 min until 35 min post) exposure to a single bout of WBC (30 s at -60 °C, 150 s at -110 °C). From both core and skin temperatures a bio-heat transfer model was applied which led to the analytical formulation of the body thermal resistance. An unsteady behavior presenting a similar time-evolution trend in the body insulative response is shown for both females and males, possibly due to the vasodilatation process following an intense peripheral vasoconstriction during the extreme cold. Females present a 37% higher inner thermal resistance than males when reaching an asymptotical thermal state at rest due to a higher concentration of body fat percentage. Adiposity of tissues inherent in fat mass percentage appears to be a key parameter in the body thermal resistance to be taken into account in the definition of appropriate protocols for males and females. The conclusions of this preliminary study suggest that in order to achieve the same skin effects on temperature and consequently to cool efficiency tissues in the same way, the duration of cryotherapy protocols should be shorter when considering female compared to male.

The effects of whole body cryotherapy (WBC) on measures of respiratory function, and their interaction with sex and anthropometry, are unknown. This study investigated ventilatory responses after WBC and examined the role of sex and anthropometric characteristics in 22 recreationally active male and female participants. Thermal sensation [TS], heart rate, blood pressure and ventilatory measures (expired volume [ V E], oxygen consumption [ V O2], respiratory exchange ratio and metabolic equivalents of task [METS]) were evaluated preand post-WBC, compared to a control condition. V E increased by 10.8 L.min -1 following WBC compared to 0.1 L.min -1 in the control session (p=.001). V O2 increased by 0.4 L.min -1 following WBC compared to 0.0 L.min -1 in the control session (p<.001). METS increased by 1.0 following WBC compared to 0.1 in the control session (p<.001). TS decreased by 2 following WBC compared to 0 in the control session (p<.001), with females' TS decreasing significantly more than males following WBC (p=.001). Following a WBC exposure, highly significant strong negative relationships were observed between fat mass index and Δ V O2 (p=.002, r=-.718), body fat percentage and Δ V O2 (p=.003, r=-.700), fat mass index and ΔMETS (p=.001, r=-.729), body fat percentage and ΔMETS (p=.004, r=-.676). Furthermore, strong, statistically significant positive correlations were observed following a WBC exposure between BSA to mass ratio and TS (p=.005, r=-.669), TS and BSA (p<0.001, r=.776) and fat free mass index and TS (p=.001, r=.745). A short exposure to WBC elicits a ventilatory response via increased V O2, V E and METS. The largest increases occur within the first minute post-exposure, but return to near resting levels one minute post-WBC. Increases inV O2, V E and METS observed post-WBC are likely due to an acute transient shivering response due to cold air exposure.