Energy Cost of Standing in a Multi-Ethnic Cohort: Are Energy-Savers a Minority or the Majority?

Abstract

BackgroundThe disease risks associated with sedentary behavior are now firmly established, and consequently there is much interest in methods of increasing low-intensity physical activity. In this context, it is a widely held belief that altering posture allocation can modify energy expenditure (EE) to impact upon body weight regulation and health. However, we recently showed the existence of two distinct phenotypes pertaining to the energy cost of standing–with the majority of a Caucasian cohort showing no sustained increase in EE during standing relative to sitting. Here we investigated whether this phenomenon is also observed across a multi-ethnic male cohort.ObjectiveTo determine the magnitude and time-course of changes in EE and respiratory quotient (RQ) during steady-state standing versus sitting, and to explore inter-individual variability in these responses across 4 ethnic groups (European, Indian, Chinese, African)DesignMin-by-min monitoring using posture-adapted ventilated-hood indirect calorimetry was conducted in 35 healthy, men (20–43 years) during 10 min of steady-state standing versus sitting comfortably.Results69% of subjects showed little or no increase (<5%) in EE during standing compared to sitting (energy savers). Furthermore, the proportion of energy savers did not significantly differ between ethnic groups, despite ethnic differences in anthropometry; with body weight as the primary predictor of the energy cost of standing maintenance (r2 = 0.30, p = 0.001).ConclusionOur results indicate that the majority of individuals in a multi-ethnic cohort display a postural energy-saver phenotype. The mechanisms by which the large majority of individuals appear to maintain sitting and standing postures at the same energetic cost remains to be elucidated but is of considerable importance to our understanding of the spontaneous physical activity compartment of EE and its potential as a target for weight regulation.

Measuring Sedentary Behavior by Means of Muscular Activity and Accelerometry

“…In addition to the activity classification for sitting, we also present an activity classification for standing. Previous studies report inconsistent findings whether standing causes a higher MET than sitting [ 24 , 39 , 40 , 41 ], and our data set displays no fundamental MET differences between sitting and standing. It therefore remains unclear whether a workplace intervention that reduces sitting also affects the activity level.…”

Standing economy: does the heterogeneity in the energy cost of posture maintenance reside in differential patterns of spontaneous weight-shifting?

“…The sample size for Study I was calculated using an online calculator (http://www.statisticalsolutions.net/calculators.php) and data obtained from previous investigations by our laboratory (Miles-Chan et al 2013;Monnard and Miles-Chan 2017). As Studies Ib and II were exploratory studies, no data previous data were available to conduct a priori sample size calculations.…”

“…As Studies Ib and II were exploratory studies, no data previous data were available to conduct a priori sample size calculations. Study III was designed to have sufficient power (α = 0.05, β > 80%) to detect a 50% increase in EE relative to resting (seated) EE based on mean resting EE values and variability measured in our laboratory during previous studies (Miles-Chan et al 2013;Monnard and Miles-Chan 2017).…”

Energy expenditure differences across lying, sitting, and standing positions in young healthy adults

“…These contradictory findings might be partially explained by the lack of a rigorous control in the experimental design, data collection (i.e. different gas collection system), and/or data analysis [8,16,17]. Other variables, such as anthropometric characteristics, body composition, age, or sex, may have also contributed to these discrepancies, but their role is largely unknown.…”