[Assessment of physical activity by means of a calorie counter combined with an accelerometer]

To establish an easy and convenient method for assessing the daily physical activity of workers, validity of a calorie counter combined with an accelerometer (KENZ Calorie Counter) was tested and compared with the method of daily survey and Stanford's interview method for energy consumption of daily physical activity. The subjects of this study were 92 volunteers. Energy expenditure of daily physical activity during 3-4 d was measured in 20 volunteers by means of a calorie counter, and the daily energy consumption was calculated from relative metabolic rates of physical activity. In the remaining 72 volunteers the energy consumption over 4-7 d was measured by means of a calorie counter and calculated from the Stanford's interview method. Correlation of the energy expenditure of daily physical activity measured by calorie counter (y) and that calculated from daily survey (x) was y = 0.74 x + 473 (r = 0.91, n = 56). Correlation of the calorie expenditure over 4-7 d measured by the calorie counter (y) and that predicted by Stanford's interview method (x) was high (y = 0.65 x + 3513, r = 0.86, n = 72). Relationship between the energy expenditure measured by the calorie counter (y) and that calculated by both daily survey and Stanford's interview method (x) showed a high correlation (y = 0.84 x + 518, r = 0.98, n = 128). These results suggest that a calorie counter combined with an accelerometer is valid for assessing the daily physical activity of workers.