As sprint running is such a basic movement for humans, it has been frequently used in research. Modern research on sprint running started in the early 1920s, and the neurological and muscular functions associated with sprint running and instinctive movements were the first to be investigated (Mero, 1992). Many studies have been conducted on improving the ability of humans to run sprint races, but as one problem has been solved, others have been raised. As a result, many issues remain to be addressed. These can be broadly categorized as : (1) mechanical efficiency in sprint running, (2) joint torque and power in sprint running, (3) muscular activity in sprint running, (4) the relationship between muscular activity and sprint running movements, (5) 100 m race patterns based on time analyses, and (6) the relationship between sprint running movements and speed. The results of studies on areas 1-3 are important for improving sprint running ability. Basically, understanding the physiological functions involved in sprinting helps to clarify the associated technical and physical factors. The results of studies on areas 4-6 provide useful information for coaches and athletes. As the level of competition is very high, effective utilization of scientific data can be the key to the success of an athlete. The present review concludes that the relationship between mechanical efficiency and sprint running cannot yet be clarified because there are no standardized methods for estimating mechanical work, and it is difficult to estimate anaerobic energy consumption during sprint running. In view of the fact that the degree of reutilization of elastic energy clearly influences mechanical efficiency, elastic energy makes less of a contribution to sprint running than it does to sub-maximal running. Muscular activity is predominantly assessed using the electromyography, but to ascertain the effects of muscular activity on sprint running, it is necessary to determine changes in the length of muscle-tendon complexes and joint torque. Baba et al. (2000) solved many of these problems and the organized complex factors involved in sprint running. In recent years, many studies have been conducted to ascertain the relationships between sprint running movement and speed based on movement analyses of numerous athletes during competitions. These studies have identified characteristic movements in good sprinters and their significance. It appears tha almost no correlation exists between sprint running speed and leg movement during the recovery phase, although a significant correlation between leg movement during the foot contact phase and sprint running speed has been identified. This type of information is extremely useful for coaches and sprinters.

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The purpose of this study was to identify the factorial structure of perceived condition fluctuation considering a time lag in a single case design applying dynamic factor analysis (DFA). The subject was a female swimmer who had won the 200-m individual medley in the 1998 inter-collegiate competition in Japan. The 15 selected items measured her perceived physical and mental condition ; the amount of training per and her regular lifestyle were recorded by herself on the "Quality Control (QC) Sheet" every day for 167 days, 24 weeks. Common factors of condition fluctuation were extracted from multivariate time-series data using DFA with the maximum likelihood (ML) method and quartimax rotation. The lag-2 variance / covariance was most optimal for DFA according to autocorrelation and partial autocorrelation of all variable. Five factors and the lag-2 DFA model were adopted considering several model-fitting indicators. The factorial structure of condition fluctuation was different in each lag model, although such factors as the amount of practice, meal satisfaction, perceived condition, and fatigue were extracted in all lag models. It was inferred that the factorial structure of perceived condition fluctuation in a female swimmer could be constructed with a time lag consideration. It was expected that changes of factorial structure accompanying time progression could be confirmed by using DFA for multivariate time-series data.

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The present study aimed to examine the differences in characteristics between two major types of resistance exercise "Strength-up type (S-type)" and "Buck-up type (B-type)" with reference to neuromuscular and endocrine responses. Eight male subjects performed leg extension exercise on separate days using the S-type or B-type regimen. The S-type consisted of five sets at 90% of one repetition maximum (1RM) with a 3-min rest period between sets. On the other hand, the B-type consisted of nine sets (divided into three parts each with three sets) at 80% to 40% of 1RM with a 30-s rest period between sets and a 3-min rest period between parts. Electromyogram (EMG) activities during the exercise, and serum growth hormone (GH) and blood lactate concentrations, thigh girth and maximal isometric strength were measured before and immediately after the exercise sessions. Percentage mEMG (the values normalized to EMG activities during maximal isometric contraction) in the B-type declined in each part with three sets, but tended to increase in the whole session, suggesting reduced neuromuscular efficiency, whereas they were maintained at higher level in the S-type. Concentrations of GH and blood lactate consistently showed marked increases after the B-type regimen, whereas they did not change a great deal after the S-type regimen. In addition, changes in thigh girth and maximal isometric strength were significantly greater in the B-type than in the S-type. The present results suggest that the characteristics of S-type and B-type resistance exercise differ greatly regarding factors related to neural adaptation and muscle hypertrophy, and that these differences affect the specific training effects between these two types of exercise.

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According to a previous study, the concept of "physical education" was introduced into Japan as a result of the influence of Westernization after the Meiji Restoration (1868). In the opening 10 years of the Meiji era, the initial concept was education for physical aspect, and as its method, both physical exercise and hygiene were used. Early in the second decade of the Meiji era, a second concept arose from the first, namely education for physical aspect being restricted physical exercise as its method. Later in the second decade of the Meiji era, a third concept - that was education for both physical and mental aspects through physical exercise - arose. However, the previous study failed to address some of the following points. Arinori Mori, a foreign service employee and thereafter the first Minister of Education in 1884, addressed his thoughts concerning military drill in the 12th year of the Meiji era (1879) ; this led to the third concept, which was subsequently termed "physical education". Therefore, the third concept which termed "physical education" had already been proposed in the early half of the second decade of the Meiji era, rather than in the latter half. To prove this, the present paper consists of the following three chapters : Chapter 1discusses the background that led Mori to reach his conclusions about military drill. Chapter 2 demonstrates that the third concept was consistent component of Mori's thoughts, and Chapter 3 shows that the third concept which termed "physical education" existed early in the second decade of the Meiji era.

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The purpose of this study was to investigate the relationships between kinematics and kinetics during sprint running, and isokinetic maximal strength of the lower limb. Sixteen male sprinters (100 m time : 10.88 ± 0.26 s) ran 60 m at maximal effort and their movements were recorded with a high-speed video camera in order to obtain the kinematic data. Ground reaction force was measured, and the joint peak torque and torque power at the right hip, knee and ankle were calculated. Isokinetic maximal strength was measured during concentric and eccentric flexion / extension of the hip, knee and anle joints at 30, 180 and 300 deg/s. The results were as follows : 1) THere were significant correlations between sprinting speed and maximal knee extension velocity during the support phase (r=-0.52, P<0.05), joint torpue of hip flexion during the recovery phase (r-0.55, p<0.05), joint torque of hip extension during the recovery phase (r=0.55, p<0.05), joint torque of knee extension during the support phase (r=0.58, p<0.05), and joint of ankle plantarflexion during the support phase (r=0.59, p<0.05). 2) There were significant correlations between isokinetic strength of hip flexion (concentric : all angular velocities, eccentric : 30 deg/s) and joint torque of hip extension during the recovery phase (r=0.53-0.64, p<0.05-0.01). Isokinetic strength of knee flexion (concentric : 180 deg/s, eccentric : all angular velocities) and joint torque of knee flexion during the recovery phase were also correlated significantly (r=0.50-0.64, p<0.05-0.01). Furthermore, there were significant correlations between isokinetic strength of plantarflexion (concentric : 180 and 300 deg/s) and joint torque of plantarflexion during the supports phase (r=0.56 and 0.64, p<0.05 and 0.01, respectively). 3) There were significant correlations between sprinting speed and isokinetic strength of flexion and extension at the hip and knee (r=0.50-0.72, p<0.05-0.01). From these results, it is suggested that isokinetic maximal strength of the lower limb influence kinematics and kinetics during sprint running. Therefore strength training is one of the keys for changing the sprinting movement subsequent to high sprint running performance.

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The purpose of this study was to examine parental influence on children's cognitive and effective attitude to competitive sports, focusing particularly on parental daily behavior from the viewpoint of the "message from parent to child". The subjects included junior soccer players belonging to a lower branch of the J League and their parents (553 families). All completed questionnaires. The result of the first analysis revealed a structure of the "message" from parents to children composed of "reinforcing self-confidence", "indirect approval", "support", "control", "value", "emotional appreciation" and "oriented result". The next analysis examined the relationship between the "message" and children's cognitive and affective attitude in terms of "intrinsic motivation", "competence", and "fear of significant other". Both the children's perception of the "message" and the parent's self-reported one were evaluated. The most significant findings were : 1) There was no relationship between parent's self-reported "message" and children's attitude, although children's perception was significantly related to children's attitude. 2) Some aspects of the "message" were related to children's positive attitude, and to other other aspects to a negative attitude. However, "emotional appreciation" and "control" were related to a positive and a negative attitude.

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