A Study on Physical Activity in Junior High School Students: Energy Expenditure in the Second-Grade Students.

The energy requirement for Japanese people 15 years old and over is publicly available (Energy Requirement in Recommended Dietary Allowances for the Japanese (Ministry of Health and Welfare 1989)) and is calculated according to activity level. The requirement for people 14 years old and younger, however, is calculated at one fixed level-level II of physical activity (Moderate), which equates to a daily activity factor of 0.5. This figure becomes the magnifying power against basal metabolism which is used to obtain energy required for living one day. Actual levels of physical activities, however, are not clearly known yet. Although some investigators have suggested that lower levels of physical activity may cause chronic disease in younger people, there is, as yet, little evidence to support this (Charney 1967, Saris 1985, Despres 1990). In order to obtain fundamental information to fill this gap, the energy expenditure (EE) and daily activity factors (DAF) of second grade students in junior high schools were estimated using the heart rate (HR) method as described in a previous study (Kida 1992).