Comparison of daily energy expenditure in young and older Japanese using pedometer with accelerometer

Abstract

Daily energy expenditure has been measured by the physical activity recording and/or the questionnaire method. Recently, the accelerometer or pedometer is used to measure daily energy expenditure. The purpose of this study was to examine validity of the pedometer with accelerometer and to compare the daily physical activity between young and older Japanese. To examine validity of the pedometer, 10 young subjects worn the pedometer (Lifecorder) on the waist and then performed the walking test. Energy expenditure was measured by the expired gas analysis during the test. Fourty-three young and 54 older subjects worn the Lifecorder on the waist during free living condition for 14 days. The intensity of Lifecorder had a high correlation with the physical activity intensity (METs) (r=0.958, P<0.001). In the free-living condition, daily energy expenditure was 2171 ± 305 kcal in young and 1617 ± 196 kcal in older (P<0.001). Total step in young was significantly higher than older (young: 9490 ± 2359 steps: older: 6071 ± 2804 steps, P<0.001). There was no significant difference in the duration of physical activities at the Lifecorder intensity 1 such as desk working, watching TV sitting on a sofa and driving a ear. However, the duration more than the intensity 2 corresponding to 2.2METs in young subjects was longer than that in older (P<0.001). We concluded that in older subjects, not only amounts of daily energy expenditure but also intensities of daily living were lower compared to the young subjects.