Basal metabolic rate and energy costs at rest and during exercise in rural- and urban-dwelling Papua New Guinea Highlanders

Abstract

Objective: (1) To evaluate inter-individual variations, regional and sex differences in the basal metabolic rate (BMR) and related variables; (2) to compare measured BMR with estimated BMR using predictive equations; and (3) to examine the net mechanical ef®ciency (NME) in step tests. Design: BMR and energy costs at rest and during step tests were measured by the Douglas bag technique of indirect calorimetry. NME was calculated from BMR and energy costs of step tests. Setting: Rural villages under subsistence agriculture and urban settlements under cash economy. Subjects: Adult males and females (n 33) including 16 rural villagers and 17 urban migrants. Interventions:Step exercise test. Results: There were signi®cant regional differences in BMR (per body weight) in both sexes. The BMR predicted by Scho®eld equation correlated with the measured BMR ( 7 1 to 3%), while the BMR predicted by Henry and Rees equations under-estimated the measured BMR by 6 ± 11%. NME was higher in urban subjects with larger body size than in rural subjects for both sexes, albeit insigni®cantly. NME tended to be higher with increased stepping level in both sexes. Conclusions: Urban migrants had lower BMR than rural dwellers, and the BMR predicted by Scho®eld equation correlated with the measured BMR in both sub-groups. Sponsorship: The United Nations University Project on People, Land Management and Environmental Change. Descriptors: basal metabolic rate; resting metabolic rate; step test; net mechanical ef®ciency; Papua New Guinea; rural and urban comparison

Energy costs of daily activities for women in rural India

“…Some earlier studies also measured energy costs of activities on small numbers of subjects [27][28][29] . However the importance of such data, although on smaller numbers of subjects, needs to be appreciated in view of the scarcity of data on energy expenditure.…”

“…This will facilitate sound comparisons of energy expenditure patterns in different populations. 29 Papua New Guinea (8) 7.51 6 0.4** RMR -resting metabolic rate. *P , 0.05 for comparison with the estimates in the present study.…”

Body composition and resting metabolic rate of Japanese college Sumo wrestlers and non-athlete students: are Sumo wrestlers obese?

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Climate variables as predictors of basal metabolic rate: New equations

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