Poster Presentation Joint Annual Scientific Meeting of the Nutrition Society of NZ and the Nutrition Society of Australia

Forearm to finger-tip skin temperature gradients contribute to resting metabolic rate in the thermoneutral zone (#P81)

Kaveri Pathak 1 , Mario J Soares 1 , Yun Zhao 2 , P A Adzika Nsatimba 1 , A P James 1
  1. Nutrition, Dietetics & Food Technology, Curtin University, Perth, WA, Australia
  2. Epidemiology & Biostatistics, Curtin University, Perth, WA, Australia

Background: RMR is always measured in the thermoneutral zone. Forearm to finger-tip skin temperature gradients are an objective assessment of thermo-neutral conditions. The aim was to explore the relationship between the two variables after controlling for many confounders.    

Methods: Data on 82 adult Australians (61 Europeans, 21 sub-Saharan Africans) were collated for this study. All participants had been measured at 25oC under standardized conditions in a temperature controlled chamber. RMR, RQ, in the ear tympanic temperatures (IET), and 30 min forearm to finger-tip skin temperature gradients (FFG) were complemented by fasting blood clinical chemistry. McAuley’s index of insulin sensitivity (McA_ISI) and presence of metabolic syndrome (MetS) were determined. FM, FFM and android:gynoid ratio was obtained from DEXA measurements. Physical activity was determined from the short version of IPAQ. Multiple linear regression modelling of RMR and RQ was conducted on several potential predictors. A backward elimination approach was used to obtain a parsimonious model, following which FFG was included as an additional explanatory variable.

Results: The participant’s characteristics were age: 45(1.67) yr., FM: 31(1.42) kg, RMR: 5763 (151)kJ/d, RQ: 0.83(0.005) and FFG: +0.65(0.30)oC. The final parsimonious model significantly predicted RMR from age, FM, FFM, ethnicity, McA_ISI and FFG. The β coefficient of FFG on RMR was 50.3 kJ/d [95%CI: 2.5, 98.2, P<0.05]. There was no relationship of FFG to RQ.

Conclusions: FFG maybe an unrecognized factor that contributes to inter-individual variations in RMR even within TNZ.

Funding source: N/A