The relationship between total energy expenditure and physical activity level in women living in an impoverished Brazilian urban area.

Abstract

This study aimed to describe how strong is the relationship between TEE and PAL in women living in an impoverished Brazilian urban area. Anthropometric, hormonal (insulin, TSH, FT4 , and FT3 ), body composition (deuterium), TEE (doubly labeled water) and PAL (metabolic equivalent task [MET]-7-day triaxial accelerometer, ActivPAL®) data were collected from 55 women (mean age: 31y, mean BMI: 27.4kg/m2 ). Adjusted-TEE models were calculated incorporating the residuals of anthropometric, hormonal, and body composition variables in the TEE, to assess the relation between MET and adjusted-TEE, through three different analyzes: linear regression, nonlinear regression and change-point regression. Most participants (89.1%, n=49) were classified as low-active. There was no association between crude TEE and MET.h/d (R2 =0.05; p=0.09). There was a positive, although weak, linear relationship between adjusted-TEE and MET.h/d (β=2705.26 kcal; 95% CI: 436.25; 4974.27; adj-R2 =0.08). A change point of this relationship was identified in the MET.h/d value of 1.53 (SD=0.02; adj-R2 = 0.13). The association between adjusted-TEE and MET.h/d before the change point (β=5101.46 kcal; 95%CI: 978.84; 9224.08; adj-R2 =0.11) was stronger than the association in the full linear model, nevertheless, it was still weak. This association stop existing when it is assessed in individuals after the change point (β=-6609.92 kcal; 95%CI: -16773.24; 3553.40; adj-R2 =0.08). These results suggest that the relationship between TEE and PAL is weak and it is not completely linear in women living in an impoverished Brazilian urban area.