In order to investigate the processes of unfavorable attitude formation against physical activities among young people, twenty-four male and female students who, out of a sample of 613 college students, indicated such a negative attitude in a questionnaire survey were interviewed. Each interview, average time length being 50 minutes, constituted a case study. The interview revealed various contributing factors, in terms of cause-result relationship, in forming unfavorable attitude against physical activities. General tendencies among the extracted backgrounds why they had come to form such unfavorable attitude may be summarized as followds: 1. Strong inferiority complex due to uncoordination and the lack of efficient sports skills prevailed. 2. Being afraid of possible failures resulting from quiet and passive personality was often a fertile bed in promoting negative attitude against physical activities. 3. Distrustful experiences in the previously involved school physical education programs, especially complaints against neglection of individual differences by the physical educators, were frequently pointed out. 4. Rigid philosophy of the physical education teachers that only faster, higher and stronger performances deserve for favorable evaluation invited strong criticism. 5. Few among interviewed had ever experienced happiness of own physical movement. Although individual right and freedom should be highly respected, negative environment against the promotion of physical education and sports among young people, such as contributing elements to produce those who unfavor physical activities must be removed from homes and schools.

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The vividness of motor imagery may be assumed to be one of the important variables that may predict the effects of image training on motor skill learning. Likewise, the special characteristics of the vividness of motor imagery are generally assumed to be different from that of the general imagery. In an attempt to construct a test battery to measure the vividness of motor imagery, a respective test (VMI test) was proposed in this study. The first purpose of the present study was to examine the relationships between the vividness of general imagery measured by Betts's test and the vividness of motor imagery by use of factor analytical techniques. The second purpose of this study was to determine the factor structure of the vividness of motor imagery. The third purpose of this study was to test some differences of the factor structure and the factor scores of VMI test between physical education major students (PE) and non-physical education majors (Non-PE). The subjects were 110 male and 80 female undergraduate physical education majors and 107 male and 98 female non-physical education majors. The fifty items of VMI test were constructed under consideration of main sensory modalities and several basic movements. All subjects were asked to evaluate their own vividness of imagery on Betts's and VMI test with five-point rating scales. The following results were mainly found out: 1. Nine factors were extracted from the factor analysis including both Betts's and VMI test items. Each of these nine factors was correlated with either Betts's test items or VMI test items, but not with the both. It seems that the vividness of motor imagery might be independent from the vividness of general imagery at some degrees. Therefore, the vividness of motor imagery should be measured at the different view point from the vividness of general imagery. 2. In the factor analysis of VMI test, five factors were reasonably interpreted. The first factor was named as visual Imagery of General Movements. This factor seems to indicate visual dominance of motor imagery. After that, the following factors were detected in order: Compound Sense-Imagery of Throwing and Hitting, Compound Sense-Imagery of Gymnastic Movements, Compound Sense-Imagery of Tapping, and Compound Sense-Imagery of Running. It seems that the first factor might be an imagery of "seeing" and the others might be an imagery of "performing". 3. Concerning the first factor of VMI test, the similar factor structures mentioned in 2 were found out both for PE and Non-PE subjects. The other factors for PE majors, however, were more specific in regard to movements than the ones for Non-PE majors. As to these results, it was indicated that characteristics of the vividnese of motor imagery factors were changeable with athletic experiences and acquisition of motor skills. 4. Non-PE majors showed significantly higher factor scores on Visual imagery of General Movements than PE majors. PE majors showed significantly higher factor scores on Compound Sense-Imagery of Gymnastic Movements and Compound Sense-Imagery of Running than Non-PE majors. Probably, an ability of vividness of motor imagery can be differentially affected by athletic experiences.

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Effects of 20 km running on heart rate, plasma and urinary catecholamines metabolism in 4 young healthy men were investigated. Plasma and urinary catecholamine concentrations were determined by high pressure liquid chromatography. The results were as follows : 1) Immediately after the 20 km running, the concentrations of plasma free noradrenaline and adrenaline were elevated up to 1.14±0.40 and 0.12±0.07 ng/ml, respectively. These concentrations fell rapidly during the recovery period and returned to the pre-exercise values at 10 min after the cessation of running. 2) Heart rate dropped from immediately after the 20km running to 5 min of recovery period. Thereafter, however, no change was observed up to 10 min of recovery period. 3) Excretion of urinary free noradrenaline and adrenaline increased right after the 20 km running. However, it recovered pre-exercise level soon after the cessation of exercise. 4) Excretion of urinary total (free+conjugated) noradrenaline and adrenaline increastd after the 20 km running. It remained elevated for 1hr after exercise and showed slow recovery from the exercise stress. 5) Excretion of urinary conjugated noradrenaline and adrenaline showed only small increases after the 20 km running, and it increased further for 1hr of recovery period. 6) Excretion of urinary dopamine (both free and conjugated) also showed only small increases after the 20 km running, and it rose further for 1hr after the cessation of exercise. 7) Free catecholamines/total catecholamines ratio (F/T ratio) before the 20 km running was 45.7% and 54.3% (noradrenaline and adrenaline, respectively). F/T ratio resulted in an increase of 64.8% and 75.3% after the 20 km running (noradrenaline and adrenaline, respectively). However, no changes were observed in urinary dopamine.

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The present study was undertaken to compare the effects of maximal dynamic and static work on forearm blood flow. Ten untrained male students, aged 19 to 20 years, participated as subjects. The subjects continued the work at loads of 1/3, 1/2 and 2/3 maximum strength of each subject until he was no longer able to follow the regular rhythm in the dynamic work, and to contract the regular length in the static work, respectively. These six work tests were conducted separately at least one week apart to remove training effects. Blood flow of the right forearm in supine position was determined by venous occlusion method before and after exhaustive dynamic and static work. It was found that peak blood flow after exhaustive dynamic work was significantly lower at 2/3 maximum strength load than at 1/3 max, while there were no significant differences among the three work loads in the static work. In addition, blood flow after dynamic work at 1/3 max 1oad was significantly higher than the static work at the same load, but it was reversed entirely at 2/3 max load. These results suggested that forearm blood flow after maximal work in the same subject varies not only with the work load, but also with the type of work, i.e., dynamic and static, even if the work load is the same.

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The purpose of this study was to determine the comparative effects of training in different postural positions on cardiorespiratory responses during exercise. The following three postural positions were taken for pedaling exercise in this study: the sitting (S), the horizontal supine (H) and the supine with legs elevated to 45° (E). Ten healthy males, aded 19-33 years, were assigned to one of the two training groups. One training group (S-training group) participated in the bicycle ergometer exercise in the S-position, and the other group (E-training group) in the E-position. Both groups trained three days in a week for 10 minutes during 20 weeks. The training intensities were corresponded to 80% of their maximal okygen uptake obtained in the maximal test in the same postural position as in the training exercise. All groups performed submaximal and maximal tests on a bicycle ergometer in the three different positions before and after training. The absolute intensities of training for the S- and E-training groups were about 972 and 666 kpm/min, respectively. This difference was statistically significant. The S-training group showed that submaximal oxygen uptake and heart rate decreased significantly at a higher work load in the S-test after training. In the E-training group, no significant differences in oxygen uptake and heart rate were noted between before and after training for either submaximal work load. Maximal oxygen uptake and total work up to exhaustion for the S-training group were markedly improved only in the S-test after training. For the E-training group, however, significant increases of maximal oxygen uptake and total work were found in the S- and E-tests.

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The trajectory of the ball after release depends upon initial ball velocity, angle of projection and hight of release. The purpose of this experiment was to determine the effects of initial ball velocity and angle of projection on accuracy of basketball shooting and to examine the relationship between these variables. The initial ball velocity, the height of ball release, and the angle of projection were analyzed through the films taken by a stroboscopic camera and a 16mm high-speed cinecamera. The degree of accuracy of the shooting was calculated by the following equation: [numerical formula] Where : Δx : X coordinates indicating the scatter of the ball at the level of hoop. v_0, θ_0 and H_0: the initial ball velovity, the angle of projection, and the height of ball release, respectively, as averaged from ten trials. ΔV, Δθ and ΔH: the values of standard deviation of the initial ball velocity (V_0), the angle of projection (θ_0) and the height of the release (H_0), respectively. It could be said from the above calculations that the accuracy of shooting is depending upon the control of initial ball velocity considerably more than the angle of projection.

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The ball stopping skills by use of foot is one of the most important and basic techniques in soccer. From the view point of mechanics, the ball stopping is a form of the collision of the ball against the foot, and the velocity of the ball after impact depends on the reduced mass of leg and the relative velocity of the foot and ball. Accordingly this study attempted to clarify the mechanism of ball controlling movements of foot, using the photographical data and signals from the force plate and the acceleration transducer fixed to the foot during ball stopping. The results may be summarized as follows. (1) The contact time of the ball against the foot at impact was rather constant, being approximately 10ms, without respect to the ball velocity befor impact. (2) The directions of movements of the foot and the ball before impact were same. But, the relative velocity of the ball and the foot increased more when ball velocity befor impact increased. (3) In the ball stopping movement, it is considered that the ill-effect of miss-judgement of the foot may be reduced in the ball controlling where the reduced mass of leg decreases.

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運動時の末梢循環系反応を明らかにする目的で, 本研究では眼底血流を手がかりとして脳血流の変動傾向を観察しようとした。眼底写真撮影は無散瞳眼底カメラにより, 安静時, 運動時および回復時のうちから5位相をえらんだ。網膜血管径は, 上耳側動静脈径および下耳側動静脈径を, 乳頭縁と動静脈血管の交点上で計測し, 乳頭径との比であらわした。また同時に心拍数と上腕動脈血圧を測定した。運動の負荷強度は各被検者の2/3V^^.O_<2max>とし, 負荷時間を30-40分とした。被検者には, 若年者として平均年齢24.1歳の男子16名, 中高年者として平均年齢50.8歳の男子9名をえらんだ。運動により網膜血管径はいずれも増加し, 運動20分時に最大となり, 若年者では平均5 -21%の増加率を示した。しかしその後は, 運動継続にもかかわらず漸減傾向を示し, 運動終了後20分を経て安静時レベルに復した。中高年者でもほぼこれと同様の傾向を示したが, 若年者に比し, 運動による網膜血管径の増加率は小さかった。この網膜血管径の増加は, 運動時の収縮期血圧変動と関係があり, 収縮期血圧が176mmHg以下の範囲では両者に有意の正相関を認めたが, それ以上の血圧値に達するとこの関係は消失した。網膜血管においては血管壁がほとんど透明で, 血管と称するものの主体は血柱であることが知られている。すなわち血管壁が伸展されるときは, 血圧が上昇したときおよび血流量が増加したときで, したがって網膜血流の動態が脳血流をよく反映するという説にしたがうならば, こうした運動時における網膜血管径の増加は, 血圧上昇をともなっていることでもあり, わずかながら脳血流量の増加を示唆するものではないかと考えた。

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