Competitive gymnasts are confronted with the problem of weight loss before a competition. They intend to decrease body fat, but not muscle. One of the most reasonable method for the purpose is a dieting. Neverthless, a dieting often leads to decrease not only body fat but also lean body weight (LBW) of which 47% is composed of muscle. That is, a dieting has the possibility of decreasing the competitive performance. The well-regulated diet is, therefore, required very much for weight loss of the gymnasts. The body composition (under-water weighing), physical working capacity (submaximal endurance capacity, muscle strength and vertical jump) and blood constituents of seven female gymnasts were measured before and after the 33 day-diet. They, ranging from 18 to 22 years of age, were high ranked athletes in Japan. The diet program was arranged by the dietitian taking gymnasts' favours into consideration. The averaged daily diet evaluated by means of a dietary recall had 1194 kcal with 54.7g of protein, 28.5g of fat and 179.9g of carbohydrate. On the other hand, the usual intakes just before the dieting were 1722 kcal in energy, 43.0g in protein, 57.1g in fat and 269.2g in carbohydrate. All the intakes of vitamins and minerals of the diet were higher than the Japanese recommended dietary allowance (RDA) . They practiced about four hours a day, six days a week, during the diet period. The daily energy expenditures before and at the last stage of the dieting were 2332 kcal and 2551 kcal on the average respectively, which were estimated through motion and time study. After the dieting body weight decreased significantly from 52.11kg to 48.35kg, of which difference was composed of 2.99kg of body fat and 0.77kg of LBW. The decrease of body fat was statistically significant, but LBW was not so. Concerning all the physical working capacities in oxygen uptake and heart rate, muscle strength except trunk extension strength, and vertical jump, there were no significant changes after the dieting. But respiratory exchange ratio (R) decreased significantly at the same work loads. This decrease suggested increased usage of stored body fat as energy during daily practice, and might support the significant decrease of body fat. Most of blood constituents were still in normal ranges in spite of significant changes. Marked change was found in serum FFA which increased three times after the dieting. This change also meant the increased usage of body fat after the dieting. These data indicated that the diet program arranged in this study proved successful and the wellregulated diet was very effective in conditioning the body composition and the physical working capacity of female gymnasts.

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In this study, the rats were subjected to a partial denervation of the soleus muscle at the age of three weeks. After this, histochemical investigations were carried out to establish what kind of changes had occurred in the differentiation of the muscle fiber type as a result of this partial drop in muscle activity.
The partial denervation was performed on the sinistral rat's soleus muscle, roughly 20% of the nerve bundles. After this, the dextral soleus muscle was used as the contralateral control muscle and excised after two, four and eight weeks, respectively. Frozen sections of muscle were stained with HE and myosin ATPase. The cross sectioned specimen were used for determining the muscle fiber count and type II fiber count.
The results thus obtained show that, compared with the contralateral control muscle, the partially denervated muscle have an approximately 5% reduced muscle fiber count two and four weeks after the partial denervation, and the type II fiber count, too, decreased to approximately 2/3 and 1/5, respectively. However, at eight weeks post-operatively, the muscle fiber count for the partially denervated muscle become almost the same as that for the contralateral control muscle, while the type II fiber count has, at this stage, recovered to approximately half its contralateral control muscle.
From these observations, it had been concluded that the reduction in muscle activity due to its partial denervation continues to act as a causal factor in the fiber type transformation untill four weeks after the partial denervation. The muscles evaluted eight weeks postoperatively showed an increase in type II fiber over the count determined four weeks after the partial denervation, and the muscle fiber count had also developed at eight weeks to value identical to that of the contralateral control muscles. Therefore, it has been concluded that the fiber type transformation in the muscle eight weeks after partial denervation is attributable to the reinnervation of the denervated muscle fibers due to the remaining intact motoneurons and to the resulting changes in motor unit size.

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The Cobb's and Ferguson's methods are widely used in order to measure scoliotic angle using the X-ray photograph. Since the scoliotic angle is detected on the bases of the positions of only two and three spines, the measured value includes various kinds of errors. Thus, the present study was designed to examine accuracy and reliability of the Cobb's and Ferguson's methods. The scoliotic angle corresponding to the Cobb's and Ferguson's method were computed using the least square approximating curve that was obtained on the basis of the positions of spines from thoracic to lumbar vertebrae.
As a result, it was found that the scoliotic angle by means of the clinical Cobb's method was closely correlated to that by the least square method with positive correlation coefficient of 0.98. On the other hands, the Ferguson's method showed less relation to the least square method. Thus, it was confirmed that the Cobb's method was more reliable for diagonsis of the scoliosis.

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As physical elements appear to relate independently to the achievement in each running performance, it may be appropriate to separate the general population into several groups when physical traits specific to the achievement in each running performance are investigated. For this reason, the following four groups were arbitrary set: Group FF with higher running speed in both 100m and 10km runs, Group SS with slower running speed in both 100m and 10km runs, Group FS with higher running speed only in 100m run, and Group SF with higer running speed only 10km run. The purpose of this study was to compare physical elements and their developmental balance between 4 different groups in terms of running ability. The subjects were 166 high school boys aged 15 to 18 (X=16.9yr) . Within the limitation of the present study, the folowing conclusions were drawn:
1) Group SS was much inferior to the other groups in many tests representing power, agility, balance, coordination, and leg muscular endurance. This group also possessed higher body fat. And scores in such traits as power and agility were significantly higher in FF group than in SF group.
2) Factor analysis showed that physical fitness domain represented by 30 variables would be divided into six factors. While group SS possessed greater body bulk (F1) than the other groups, it had much inferior ability in power and agility (F5) . Cardio-respiratory function (F4) was significantly better in FF and SF groups as compared with SS and FS groups. However, no distinct differences existed beween groups in any of static strength (F2), body linearity (F3), and flexibility (F6) factors.
3) Finally, this study supports the hypothesis that the developmental balance of physical elements is specific to each running group. Particularly, it is interesting to note that group SS showed higher scres in body bulk and lower scores in cardio-respiratory function, power and agility as compared with scores in the other factors.

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Oxygen uptake and cardiorespiratory parameters were measured during submaximal and maximal work in flume swimming, bicycling and treadmill running, in order to compare physiological responses of swimmers to those three types of exercise. Subjects were divided into three groups according to the level of swimming training, i, e., 5 less trained water polo players (group A), 5 male well trained college swimmers (group B) and 14 male elite swimmers (group C) .
V_2max during swimming in group A (3.11 1/min) was 5% lower than during bicy cling, while those in group B (3.63 1/min) and C (4.12 1/min) were 9% and 11% higher, respectively. Comparing with running, Vo_2max during swimming was 19% lower in group A, and was about the same in group B.
V_E and V_E/ Vo₂ were lower during submaximal and maximal swimming compared with bicyling and running, in all groups except the maximal work of group C. Lower V_E during swimming resulted from lower f as well as lower V_T. The difference in V_A between during swimming and during running, bicycling was small compared with that in V_E.
Q during swimming increased almost linearly with Vo₂ in all groups. At a given Vo_2submax, Q was about the same in three types of exercise. Q during maximal swimming in group A (19.7 1/min) and B (21.3 1/min) were similar compared with bicycling, but were 16% and 11% lower compared with running, respectively. Q_max during swimming in group C (23.8 1/min) was 5% higher compared with bicycling.
HR increased almost linealy with Vo₂ in all exercise. At a given Vo_2submax, HR was 4-5 beats/min less during running than during bicycling, and was 10-20 beats/min less during swimming than during those two types of exercise. HR_max was lower during swimming compared with bicycling or running in all groups. A similar Q at submaximal work during three types of exercise resulted from higher SV and lower HR in swimming.

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