LAUSR

Different environments might influence energy expenditure (EE) from physical activity (PA) monitors. We evaluated and compared the test-retest reliability and criterion validity of the Sensewear mini (SWAmini) and Actiheart (AH) to estimate EE in two climatologically different countries, i.e. Suriname (tropical rainforest climate) and Belgium (oceanic climate). Fifty-six healthy participants (18–40 years) were recruited (Suriname: n = 30; Belgium n = 26). On three occasions they completed a standardized protocol including sitting, standing, low (LOW), moderate (MOD) and vigorous (VIG) intensity walking on a treadmill whilst wearing both PA monitors and a metabolic measurement system. The first session was a familiarization test, the second and third were used for reliability [intraclass correlation (ICC)] and validity analysis (mean absolute percentage error calculations, Bland-Altman, and scatterplots). Comparisons between countries were done by independent sample t-tests. We found i) fair to excellent SWAmini reliability [ICC between 0.41 (0.04–0.70) and 0.97 (0.92–0.99)]; ii) good to excellent AH reliability [ICC between 0.72 (0.45–0.87) and 0.96 (0.92–0.98)]; iii) underestimation of EE for all activities except for LOW by SWAmini; iv) in Belgium EE underestimation was greater by the SWAmini for sitting (Suriname: 5% ± 20% vs Belgium: 15% ± 12%) and by the AH for VIG (Suriname:18% ± 26% vs Belgium:37% ± 16%) v) overall poor agreement between AH and metabolic measurement system. The reliability of the PA monitors is between fair and excellent in both environments. There is a difference in validity between the two environments for sitting activities by the SWAmini and for VIG by the AH.