The purpose of this study is to discuss the effects of aging and exercise on aerobic capacity in the elderly and the procedure for encouraging sedentary elderly to engage in a health promotion program based on aerobic exercise. Regular proper aerobic exercise training, even when started as an elder, induces an increase in maximal oxygen intake and lactate threshold (or ventilatory threshold) by enhancing ventricular diastolic function and oxidative capacity in muscle ; and reduces the risk factors of lifestyle related diseases. There was a need for a simple test for determining aerobic capacity and exercise prescriptions in community-dwelling elderly. We recommended two methods for this purpose : one is to determine DPBP and the other is to estimate work rate at a certain concentration (rest plus 0.1 mmol /l ) of the blood lactate based on it just after 2 A stage step exercise. Both work rate can be used not only for evaluation of the aerobic fitness level, but also a safer and effective exercise intensity to elucidate the benefit of aerobic exercise. These tests were very simple and can determine 5 to 10 people simultaneously.

Angiotensin I converting enzyme (ACE) gene Insertion/Deletion (I/D) polymorphism was first shown as a genetic factor which influences human physical performance in 1998. Since then, various gene polymorphisms which influence physical performance and trainability have been reported. ACE is a key enzyme which produces angiotensin II in the renin-angiotensin system, and its activity was determined by I/D polymorphism. Many studies indicate that the I/I genotype is frequently found in elite endurance athletes, while the D/D genotype is frequently found in power-oriented elite athletes. Longitudinal studies show that the D/D genotype may contribute to enhanced strength trainability. However, it is still unclear whether the I/I genotype enhances endurance trainability. Therefore, the ACE gene I/D polymorphism can be a genetic factor which influences human physical performance.

The decrease of muscle glycogen may be useful for the improvement of endurance performance. Intense anaerobic exercise requires a high rate of glycogen utilization, but consecutive intense anaerobic exercises induce a pronounced decline of external power and muscle glycogen consumption. We hypothesized that a long rest period between consecutive intense anaerobic exercises may aid in sustaining external power and glycogen consumption. Secondly, we hypothesized that active rest (AR) during the long resting period may be more effective than passive rest (PR).Six subjects performed four 30-second Wingate tests (WAnT) with a 4-minute recovery between each bout (Consecutive method). The subjects also performed a similar exercise procedure, but with a 30-minute seated resting period after the second bout (PR method).The other six male subjects performed four 30-second WAnTs with a 4-minute recovery between each bout, with 30-minutes of cycling at 40% VO₂max after the second bout (AR method). The subjects also performed PR method.The total work during the third and fourth bouts was greatest under the AR condition, followed by the PR condition, and finally the Consecutive method (p<0.05 for all comparisons). Blood lactate concentration during resting period was significantly lower, while muscle glycogen consumption was greater AR method than PR method (p<0.05 for both).A long resting period between consecutive intense anaerobic exercises may prevent the decline in external power and work. Additionally, AR has more favorable effects on muscle glycogen consumption, resulting in very low muscle glycogen levels, even with a small total amount of exercise.

Evaluation of the physical fitness level of children and adolescents must include consideration of individual growth rates. This study evaluates the relationship between height and physical fitness in a large sample of 6-17 yr students. Physical fitness test scores were calculated for every 1 cm height group and used to generate quadratic regression equations. Physical fitness data reported by the Ministry of Education, Culture, Sports, Science and Technology in Japan (MEXT) were compared with estimated values obtained using our regression equations. The differences between the values reported by MEXT and our estimated values were very small. Comparison of physical fitness T-scores calculated based on school grade averages with T-scores based on means calculated using our regression equations indicated that shorter height students had lower T-scores if school grade averages were used for the calculation. In conclusion, in elementary and junior high school students, it is important to evaluate physical fitness level relative to individual physical growth.

Recent studies indicate that exercise with a low muscle glycogen state enhances exercise-induced metabolic adaptation. However, it is unclear whether metabolic adaptation is involved with muscle glycogen depletion level. In this study, we investigated the effects of prior muscle glycogen depletion level on metabolic response during acute continuous exercise. Seven men completed two experimental trials consisting of two exercise sessions per day. During the first session, participants performed either intermittent exercise (IE) at VO₂max (the IE-CE trial) or continuous exercise (CE) at lactate threshold (the CE-CE trial). During the second session, participants performed 60 minutes of CE at lactate threshold. During this second session, fatty acid oxidation (FAO) was calculated. To determine muscle glycogen content and PGC-1α and PDK-4 mRNA abundance, muscle biopsies were taken at rest after the first session and 2 hours after the second session. After the first session, muscle glycogen content was significantly lower in the IE-CE trial (38.1±5.0 mmol/kg w.w.) than in the CE-CE trial (56.7±10.2 mmol/kg w.w.), P<0.05. FAO was higher in the IE-CE trial than the CE-CE trial at baseline and 15 minutes after the second session (both P<0.05). PGC-1α mRNA abundance increased after exercise (IE-CE, 5.9±2.5; CE-CE, 2.6±1.3-fold; P<0.1). PDK-4 mRNA abundance increased significantly after exercise (IE-CE, 22.2±8.8; CE-CE, 31.5±10.6-fold; P<0.05). PGC-1α and PDK-4 mRNA were not significantly different between the trials. In conclusion, continuous exercise with a slightly muscle glycogen-depleted state induced similar level of PGC-1α and PDK-4 mRNA expression, but attenuated FAO, compared to exercise with a moderate muscle glycogen-depleted state.

Recent health guidelines suggest that children should accumulate 60 minutes of physical activity (PA) of moderate to vigorous intensity every day. The purpose of this study was to assess PA on weekdays, in addition to physical fitness, in elementary school children during short-term extracurricular activities (EA). Children from an elementary school (n=160) who carried out EA were assigned to the EA group, and children from the neighboring elementary school (n=210) comprised the non-EA group. A physical fitness test was applied to evaluate physical fitness in pupils. Moreover, 48 children (EA, n=24; non-EA, n=24) wore a pedometer with a uniaxial accelerometer to determine the amount of PA and time spent in moderate- to vigorous-intensity PA. The PA of EA was evaluated with the exception of the short program (10 min). Jogging distance of the EA was 1357 ± 333 m, average speed was 170 ± 42 m/min. The estimated energy consumption of jogging was 55 ± 19 kcal. Multiple items of the physical fitness test scored significantly higher in the EA group than in non-EA subjects. Total step counts were 15485 ± 1915 steps/day for the EA group and 12363 ± 2464 steps/day for the non-EA group on weekdays (p<0.001). Time spent in moderate- to vigorous-intensity PA on weekdays was 61.6 ± 10.0 min/day for EA children and 46.5 ± 12.9 min/day for non-EA children (p<0.001). In addition, the extent of PA in the EA group was higher than the amount recommended for children in general. This study suggested that short-term EA are related to both the fitness and PA levels of elementary school children.

The inter of this study was to observe the effects of training on histochemical and biochemical properties in the skeletal muscle fibers.
Wistar strain albino rats were assigned to endurance (E), sprint (S) and control (C) group at 4 weeks old. Animals of trained groups were trained by treadmill for 12 weeks. After training, all animals were sacrificed and M. Soleus (SOL) and M. Extensor Digitorum Longus (EDL) were taken out.
Using histochemical staining methods for Hematoxylin and Eosin, Actomyosin ATPase and Succinate Dehydrogenase (SDH), area and composition of the three muscle fiber types were examined. Furthermore, the chemical properties of glycolytic and oxidative enzyme activities were examined.
The results obtained were as follows:
1. The E and S trained groups, respectivelly, showed lower increase of body weight than the control group.
2. Hypertrophy of all fiber types in EDL were observed in the both trained groups. Area of SO fibers in SOL were also increased in the E group as compared to the C group.
3. The differences observed for fiber composition among the three groups. The rate of FOG fiber in SOL decreased significantly in the both trained groups as compared to the C group. The rate of SO fiber in both muscles were slightly higer for the E group relative to the C Group, but these differences were no significant. However, in the E group significant increase was observed for oxidative enzyme activity. The Phosphofructo-kinase activity in EDL of the S group was significantly higher in comparison to the other groups.
These results suggested that there is the discrepancy between histochemical proper-ties and biochemical properties in the effects of training on skeletal muscle fibers and that the necessity of histochemical and biochemical analysis.

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. Fourtythree 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±196kcal 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 car. However, the duration more than the intensity 2 corresponding to 2.2 METs 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.