ENERGY EXPENDITURE, BODY COMPOSITION AND MAXIMAL OXYGEN UPTAKE IN MIDDLE-AGED JAPANESE WOMEN WHO HAVE LONG-TERM HABITS OF EXERCISING / 体力科学

The purpose of this study was to examine the effects of long-term habitual exercise on daily total energy expenditure (TEE) and its components, body composition and maximal oxygen uptake (VO₂max) in middle-aged Japanese women. Twenty-eight subjects aged 39 to 58 years were assigned either to a nonhabitual exercise group (Control ; n=12) or a habitual exercise group (Exercise ; n=16). TEE, physical activity level (PAL) and the daily physical activity energy expenditure (PAEE) were assessed by doubly labeled water (DLW) method. The exercise-induced energy expenditure (ExEE) and nonexercise-induced energy expenditure (NExEE) were evaluated based on the activity record investigation conducted simultaneously during the DLW measurement period. The result follows that TEE was significantly (p<0.01) higher in the Exercise group (2520 kcal · day^-1) than in the Control group (1921 kcal · day^-1). There was no significant difference in basal metabolic rate between the groups. PAEE and ExEE were significantly higher in the Exercise group than in the Control group (p<0.01). Habitual exercise induced an increase in TEE without resulting in a compensatory reduction of NExEE. The percentage body fat (fat%) was significantly lower in the Exercise group (25.5%) than in the Control group (30.9%). VO₂max was higher in the Exercise group (1788 ml · min^-1) than in the Control group (1417 ml. min^-1). After correction for body weight, fat% was negatively associated with TEE (p<0.01), PAEE (p<0.01) and ExEE (p=0.05), while VO₂max was positively associated with TEE (p<0.05), PAL (p<0.05), PAEE (p<0.05) and ExEE (p<0.01). These results suggest that habitual exercise is associated with the increase of TEE, the improvement of body composition and VO₂max. The improvement of VO₂max was mainly caused by the increase in ExEE, indicating that the exercise intensity is important to the improvement of cardiorespiratory endurance fitness.

MEASUREMENT OF TOTAL ENERGY EXPENDITURE IN JAPANESE FIREFIGHTERS UNDER NORMAL WORKING CONDITION USING THE DOUBLY LABELED WATER METHOD / 体力科学

This study examined total energy expenditure (TEE) of Japanese firefighters under normal working conditions, and also evaluated several field methods for measuring TEE in comparison with the doubly labeled water (DLW) method. Ten male subjects belonging to Tokyo metropolitan firefighters departments, aged 30.0±2.8 yrs (mean±SD), were monitored for five consecutive days. While TEE was assessed by an accelerometer (AC) and activity records (AR) in additoin to DLW, energy intake (El) was evaluated by dietary record. There were three emergency calls over the assessment period, but no real operation of fire suppression. TEE obtained by the DLW method (4009±611 kcal/d) was significantly higher than that estimated by AC (2531±186 kcal/d) or AR (3704±476kcal/d) ; but significantly correlated with AR (r=0.876, p<0.01) . El (3539±286 kcal/d) showed no significant relationship with DLW. These results suggest that compared with AC, AR would be more feasible for estimating TEE of firefighters, who perform special activities carrying heavy equipment. The mean value of physical activity level (PAL) (2.2±0.3) indicates that firefighters can be categorized as heavy workers like soldiers or policemen.