Behind the discussions on the content of Physical Education in the late 60s, there was some consideration of the scientific approach to education. At that time there was some debate about what should be taught for Physical Education. Also, it was maintained that evaluation in a Physical Education class should not be based on performance in a certain sport, but on the subject matter content taught in the class. Discussing this issue, the author concluded that scientific research methods and findings of sport sciences should be taught practically in Physical Education classes. However, in order to specify the appropriate content of Physical Education, we still need to consider 1) the relationship between cognitive ability of children and the object of cognition, 2) a teaching method appropriate to the object of cognition, and 3) the reasons for teaching specific aspects of Physical Education. Answering these questions will also help to explain why people should do sport. As our social, historical and cultural contexts are different from those of Europeans and Americans, we should not take the same viewpoint as them. Based on our own experience of the transformation we should transmit our thoughts to the world to change sport for them.

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Thirty-five male high school students were divided into three groups that showed comparable performances in the 3,000-in run, and each group was coached in a total of 6 classes by the all-out method, in which the students ran a certain distance within a limited time at full exertion, inner/outer track (I/OT) method, in which the duration of exercise was nearly equalized by having slower/faster runners use the inner/outer running tracks, and the RPE (ratings of perceived exertion) method, in which the students ran according to the RPE scale. The effects of the three coaching methods were compared in terms of performance in the 3,000-m run, physiologic responses, and the results of a questionnaire. 1) The time for the 3,000-m run improved by 7.4% when the all-out method was used, by 5.3% using the I/OT method, and by 3.1% using the RPE method. 2) The mean heart rate (HR) during running was significantly higher in the all-out group (176.2 beats/min) and I/OT group (173.8 beats/mm) than in the RPE group (156.4 beats/mm). The %Vo_2 MAX estimated from these heart rates was 67.3% in the all-out group, 66.4% in the I/OT group, and 59.7% in the RPE group, consistent with the performance in the 3,000-m run. The duration of endurance running was longest in the RPE group and shortest in the I/OT group. Therefore, there was no significant difference in work among the three groups. Significant correlations were observed between RPE and the sense of achievement, between HR and the sense of achievement, and between HR and RPE, suggesting that the sense of achievement reflects the exercise intensity. The physical condition tended to decline with repetition of endurance running in the all-out group and I/OT group, but tended to improve in the RPE group. 3) Before the subjects were coached in endurance running, they tended to like gym classes but to dislike endurance running. After coaching, dislike of endurance running increased in the all-out group, but it was considerably reduced in the I/OT group, and was, in fact, reversed in many students in the RPE group. These results suggest that the like and dislike of en durance running are caused by mental and safety factors rather than the characteristics of endurance running or physical or technical factors. 4) Coaching methods for high school students should be selected on the basis of the aim of training.

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The purpose of this study was to examine whether excess CO_2 output during and after short duration-high intensity exercise would be a valid indicator of bicarbonate buffering action and to investigate its relationship with exercise performance. Seven competitive university sprinters performed 40-s maximal cycle ergometer sprinting. Excess CO_2 output during and after exercise was obtained through respiratory gas analysis. Furthermore, lactate concentration, pH, bicarbonate ion concentration ([HCO_3^-]) and CO_2 partial pressure were obtained through arterial blood sampling. Excess CO_2 output per unit time (Excess Vco_2) was calculated by subtracting Vco_2 from VO_2 during and after exercise. Peak power and mean power were measured as an index of exercise performance. The process of the ExcessCO_2 accumulation was fitted to the process of the [HCO_3^-] decrease during and after exercise. ExcessCO_2, calculated as the sum of Excess Vco_2 from the start of exercise until 10 mm after exercise, was significantly correlated with [HCO_3^-] decrease (r = 0.904, p<0.0l). A significant correlation was also demonstrated between Excess CO_2 and mean power during the 40-s maximal cycle ergometer sprinting (r = 0.859, p<0.0l). These results suggest that Excess CO_2 during and after short duration-high intensity exercise is a valid indicator of bicarbonate buffering action, and that it could be an important factor in determining exercise performance.

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Endurance-trained athletes with higher aerobic power (Vo_2max) have a large-sized left ventricle (LV) and aorta (Ao). We therefore hypothesized that the individual variability of Vo_2ax can be estimated using resting LV and Ao dimensions. In looking at this question we performed a laboratory-based cross-sectional study to determine the relationship between Vo_2max, LV dimensions, and Ao dimensions in young subjects with wide ranges of physical activity status. One hundred forty-two healthy young men (20-35 years), who were either sedentary, recreationally active or endurance-trained, participated in the cross-sectional study. Subsequently, a meta-analysis approach was used to collect 28 studies involving 58 groups and 816 subjects. LV and Ao dimensions were determined by echocardiography at supine rest. In the cross-sectional study and meta-analysis, LV end-diastolic diameter (LVEDD) and end-systolic diameter (LVESD), posterior wall thickness (PWT) and inter-ventricular septum thickness (IVST), and Ao diameter (AoD) were positively and significantly correlated with Vo,max. When we performed a stepwise regression analysis in the cross-sectional study to determine independent predictors of Vo_2max, the variables entered were LVEDD, AoD, and PWT, which together explained 60-70% of the variability. Furthermore, we attempted to develop equations for predicting Vo_2max. Multiple regression analyses using LVEDD, AoD, and PWT as the explanatory variables for predicting Vo2max yielded the following equations. Vo_2max (ml・min^<-1>・kg^<-1>) = 49.2 LVEDD (mm/kg) + 27.2 AoD (mm/kg) + 43.9 IVST (mm/kg) -2.6. These results suggest that the variability of Vo_2max can be accounted for by differences in both left ventricular and aortic structure. Furthermore, echocardiography at supine-rest was useful for evaluating maximal aerobic power, specifically for young healthy men, who demonstrated a wide range of trained states.

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Peter Villaume (1746-1825) was a philathropist who aimed at acquiring "power" through bodily education. This paper focuses on his theory of bodily exercise, especially running exercise, that provided the "power". Villaume considered that "power" was "the drive, the rapidity of the blood stream, and the sensitization of nerves", and that the strength of the muscle and skeleton was the "tool" of the power. Thus bodily education for humans must not be to train "the power of the muscle and skeleton", but to activate "the drive", to make the blood stream more rapid, and to sensitize the nerves. Villaume's method of bodily exercise was based on this approach to physical education, whereas GutsMuths's method was based on acquiring "the power of the muscle and skeleton". I therefore compared Villaume's method with GutsMuths's method of bodily exercise with reference to running. I concluded that "running" as defined by Villaume was exercise based on practice in his studies on "Philathropen". However, when we read descriptions about "running" by Villaume from the viewpoint of his theory of exercise, with the purpose of fostering "power", we notice some characteristics that are different from traditional opinions. Villaume considered it important to develop certain kinds of power through exercise. According to Villaume, it was important for children to experience "the realization" of "running" under various conditions. That is to say, children would be able to realize the progress of their own "powers". Thus, it seems that Villaume was eager to cultivate the "power" of children through running. On the other hand, GutsMuths's approach did not require a teacher to think about differences in individual levels of power and the speed of improvement in exercising. GutsMuths instructed the teacher to pay attention to "height" and "time" or "distance" when teaching running. And it seemed that the purpose of running was to improve the record for time and distance, making children run "as fast and long" as possible. Today when the philosophy of "the power to live" is fashionable, it is possible to put some meaning to Villaume's method of bodily exercise based on "power".

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To determine the daily energy requirements of soccer players, we measured total energy expen-diture (TEE) in nine Korean Professional Football League players (mean ± SD; age 29 ± 4 years, height 180 ± 7 cm, body mass 75.7 ± 10.3 kg) during 7 days of a competitive season using the doubly labeled water (DLW) method. Energy intake (EI) was simultaneously estimated from 7 days of dietary records. Mean TEE and EI were 16.8 ± 2.4 MJ/day (4,013 ± 583 kcal/day) and 16.4 ± 1.6 MJ/day (3,941 ± 382 kcal/day), respectively. El was highly correlated with TEE (r = 0.747, p<0.05) and was also no significant difference. The physical activity level (PAL = TEE/estimated basal metabolic rate) was 2.22 ± 0.28. We discussed the energy requirements of soccer players during a competitive season based on PAL of both Korean and Japanese Professional Football League players.

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The purpose of this study was to examine the relationships between the decline of running speed during a marathon race and the changes in running economy, running mechanics and muscular strength and power expended in the race. Thirteen healthy males were measured for oxygen consumption (VO_2), respiratory exchange ratio (RER) and running kinematics (stride frequency, stride length, support time and non-support time) during treadmill running (200 m/min, 3 min), maximal force and rate of force development (RFD) of isometric knee extension (ISO), and jumping height (JH) of counter-movement jump (CMJ) and 5-rebound jump (5RJ) before and after a marathon race (42.195 km). 1) In all of the subjects VO_2 during treadmill running tended to increase. RER was significantly decreased, and non-support time was significantly shorter after the race. Maximal force and RFD of ISO and JH of CMJ and 5RJ were significantly lower after the race. Contact time of 5RJ was also significantly longer. 2) There were no relationships among the changes in running economy, running mechanics and muscular strength and power. 3) When the subjects were divided into two groups according to relative change in running speed due to the race, the KEEP group (n=6, %change: 0.44 +/-2.6%) showed a significantly different RER, non-support time, maximal force and RFD of ISO and contact time of SRI, whereas the DOWN group (n= 7, %change: -21.8 +/-16.8%) showed a significant increase in VO_2 during treadmill running, and significantly different RER, and muscular strength and power measurements. These results suggest that the decreases in running economy and muscular strength and power, and the changes in running mechanics may cause the decline of running speed during the race. However, because the interrelations among these parameters remain unclear, further research will be required to develop training methods that can minimize these changes.

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