The purpose of this study is to conduct the examination of heart rate and speed variations with respect to the various interval trainings of swimming. One trained, one post-trained and one untrained swimmers were employed for this study. The experiment was conducted during the summer of 1968. The temperature of atomosphere varied from 30°C to 33°C and that of water from 27°C to 29°C.
The data of heart rate were obtained from the record of ECG. Two electrodes or ECG consisting of silver cups of 10mm in diameter were attached to the skin over sternum. In order to avoid mechanical and electrical disturbances, the electrodes were tightly fixed through the following procedures;
1) The electrodes were pasted on cleaned skin with ECG jelly.
2) The adhesive plaster was placed over the electrodes.
3) The adhesive plaster was coated with wax.
The wire of 20 meters was used to connect the electrodes and the recorder. On trial of interval training was consisted of two phases; 1) The active phaseTo swim 50 meters according to his swimming ability. 2) The rest phase.To take a 0, 5, 10, 20, 30, 45 or 60 seconds interval between each 50 meters swimming. Each trial of training was repeated ten times.
Results are as follows;
1) The longer the rest period is, the higher the swimming speed is.
2) All swimmers swim 50 meters at 60-80% of their maximum speed and the percent of the trained is higher than that of the untrained.
3) Maximum heart rates of the trained, the post-trained and the untrained during tenth swimming are 188, 180 and 173 respectively, which are the same in every trial.
4) Decreasing rates of heart rate during the rest period are 10 under in 5-10 seconds interval, 15-25 in 20-30 seconds interval and 20-50 in 45-60 seconds interval,

Three middle-aged men (55-58 years) trained for 50 weeks. Exercise consisted of twelve minutes walking on the motor driven treadmill at the load of 70% of maximum oxygen intake, three times per week.
Evaluations for maximal and submaximal work were made at 5-week intervals using treadmill walking method. Mean maximum oxygen intake improved 29.5% (26.1-39.7 %) over the 50-week period from 1.93 to 2.50 l/min, Mean maximum oxygen intake per body weight improved 24.5% from 34.9 to 43.5 ml/kg.min.
But through the training session, the maximum values of maximum oxygen intake were obtained over the 25-week to 35-week period on each subject. After that period, maximum oxygen intake were unchanged or slightly dropped neverthless the training was continued.
As the linear relationship was found between the oxygen intake and heart rates during exercise, the regression equations were calculated on each maximal test. The regression line might represent the oxygen pulse on each heart rates level during exercise. The oxygen pulse improved clealy also during submaximal work. The improve-ment of oxygen pulse were distinctive to 25-35 week period and after that no change were occured.
In the submaximal test, there was seen clear improvement of efficiency during 20 minutes walking at the load of 70%, 50%, 30% of maximum oxygen intake respectively, even after the period that the increment of maximum oxygen intake could not be caused by training.

The effect of endurance training on aerobic power and the relationship between aerobic power and running performance were investigated longi tudinally on eleven junior runners for 5-7 years, starting from the age of 14, 15 yr. Maximal aerobic power was measured with the subject running on a motor-driven treadmill. The subjects were divided into two groups (Group I, II) .
The results were as follows ;
1) Group I (superior junior runners) showed greater aerobic power and better running performance compared to Group II (good junior runners) . The values for Group II were between those for Group I and for ordinary school boys.
2) Aerobic power for Group I increased from 14, 15 to 18, 19 years old, while aerobic power for Group II decreased to the similar values of the ordinary school boys after stopping the running training.
3) Greatest value for aerobic power was obtained on Subject A as follows : 3.63 1/min (61.5 ml/kg. min) at 14.7 yr of age, 4.67 1/min (74.6 ml/kg. min) at 17.8 yr, 5.04 1/min (76.3 ml/kg. min) at 20.7 yr.
4) Improvement in running performance was closely related to the increase in aerobic power (1/min) for the junior runners during the age of 14 to 18 yr.

One third to one fourth of main life is devoted to growth and motor development. An urbanization and a lack of big muscular activity in childhood may lead to impaire development of individual physical activity and attendant function.
A riding on a bicycle is the play which is so great favorite with the children. The purpose of this study was to determine the riding on the bicycle or cycling in children from view point of physiological aspect.
In this experiment, at first, using a special electric device maximum and ordinary cycling speeds were measured. Forty children, aged 5 years of old of male and female, were employed as subject. The maximum and ordinary cycling speeds were 3.40m/sec-4.45m/sec and 1.30m/sec-1.65m/sec for male, 2.94m/sec-3.68m/sec and 1.20m/sec-1.52m/sec for female, respectively. There was a difference in the cycling speed among the size and type of bicycle, sexuality, and physical fitness level of subject.
It is the further the purpose of this study to determine the oxygen intake and cardio response of the schoolboys and schoolgirls, aged 6-9 years old, during cycling with various speeds at different lanes. During cycling at flat lane heart rate and estimated oxygen intake were 113 beats/min-128 beats/min and 0.39 l/min-0.48l/min, respectively. It could be said that the physiological intensity of cycling is insufficient to improve the aerobic working capacity of children.
Making comparison of the oxygen intake and heart rate between the flat lane and upward slope, those for upward slope were much more than for the flat lane.

As well known, the adreno-sympathetic hormone - catecholamine - plays an important role in maintaining the stability of “milieu interieur”. Accordingly, a marked change may occur in catecholamine secretion in case of prolonged strenuous exercise such as marathon race where is required remarkable augmentation of cardiovascular functions. The authors had an opportunity of examining the physiological functions of all the participants in the First Tokyo International Women Marathon Race held on November 18, 1979, and collected urine samples from them before and after the race to evaluate the physiological load of the race in each woman participant by changes in urinary excretions of catecholamine metabolite (VMA) and some other substances.
As for the subjects of examinations, 19 foreign runners were 31.1 years of age on the average (ranging from 20 to 48 years) and their average Rohrer's Index was 119.0, while 33 Japanese runners were 27.8 years of age on the average (ranging from 18 to 42 years) and their average Rohrer's Index was 125.8. The urine samples at rest were collected at 8 a.m. on the day before the race after more than 10 hours fasting, and the samples after running were collected in 30 minutes after finishing the race. Just after the collections, the authors made determinations of the urine volume and pH and qualitative tests for sugar, protein, occult blood, Keton bodies and bilirubin. Then the determinations of VMA were made by Pisano's method. The resulte obtained were compared among six groups classified by the performance, viz., the order of the arrival. The classification was made as follows : 1) 1-5, 2) 6-10, 3) 11-15, 4) 16-20, 5) 21-25 and 6) 26-46. The comparison was also made between the foreigners and the Japanese.
Results:
Although there could be no significant correlation between the performance and the age or physique, the Rohrer's Index was smallest in Group 1) and largest in Group 6) .
The qualitative urine tests disclosed no marked change due to the running but protein less than 300 mg/dl was detected in the urine after running in 31 out of 40 runners. This fact seems to suggest that their physiological loads were considerably heavy. The urine volume on the average showed a decrease from 41.5 ml/hr at rest to 16.3 ml/hr after running, viz., 60.7 % decrement. The decrement was 53.2 % in the foreigners while it was 65.3 % in the Japanese. The urine volume was rather larger in Groups 5) and 6) than in the others. The urine pH on the average showed a decrease from 6.4 at rest to 5.6 after running, viz., 12.5 % decrement, and the decrement was 6.9 % in the foreigners while it was 14.9 % in the Japanese. Regarding the relation between the performance and the urine pH, there could be noted a tendency, the upper the ranking of the group, the smaller the change in pH.
The urinary excretion of VMA on the average of all the runners showed a striking increase from 155.8 mg/hr at rest to 383.1 mg/hr after the running. The increase due to running was 121.4 % in the foreigners while it was 144.1 % in the Japanese. Regarding the relation between the performance and the VMA excretion, Group 1) showed no increase in the excretion on the average, while the other groups generally showed 100 % - 200 % increase in the excretion.
On the basis of the above-mentioned findings, it was presumed that the physiological load of the marathon race was heavier in the Japanese runners than in the foreign runners, and in the lower ranking groups than in the upper ranking groups of the performance. In other words, the foreigners who showed excellent performance seemed to be highly adapted to the prolonged strenuous exercise by training and to have a regulatory mechanism of metabolism so efficient as to cope with heavy physiological load by small increase in catecholamine secretion.

The purpose of this study was to determine maximum oxygen intake and its relation to body weight of Japanese ordinary adolescents who consisted of 266 boys and 280 girls (12-18 years of age) living in Nagoya City.
The progressive treadmill exercise test was chosen as a work stimulus. Treadmill test was made with a constant slope of 8.6%. During the first 2 minutes, the treadmill was set in motion at a certain speed (160m/min for boys and 140m/min for girls), and then the speed was increased by lOm/min every succeeding minute until exhaustion. Expired air during running was collected in Douglas bag every 1 minute upto exhaustion. Then sampling gas was analyzed by means of a Beckman oxygen and carbon dioxide analyzer. The heart rate was calculated from ECG during running and the respiratory rate was determined with the aid of thermister attached to the inside of the mask. All experiments were performed in the afternoon (PM 3 : 00-5: 00) during the winter seasons from 1968 to 1970.
The results obtained in this study were as follows;
1) The mean value of maximum oxygen intake of the boys remarkably increased with age until 18 years of age. The maximum value was 2.81 l/mmn at 18 years of age. On the other hand, the mean value of the girls was almost constant over a wide range of ages from 12 to 18 except between 16 and 17. The maximum value was 1.941/min at 17 years of age.
2) The correlation coefficients and the regression equations were calculated between maximum oxygen intake and body weight.
Boys r=0.883 Y= 0.0457X+ 0.0902 ± 0.3094 (n; 260)
Girls r=0.595 Y=0.0149X+1.0648±0.2565 (n; 288)
Where Y is maximum oxygen intake in l/min and X is body weight in kg. The same correlation coefficients and regression equations were calculated relating to sex and age. As for boys, the coefficients of “X” in the regression equations increase with age from 0.0227 at 12 years of age to 0.0468 at 18 years of age. On the other hand, there was no distinct inclination in the regression equations of the girls.

The present study was intended to determine max. Vo₂ and its relation to body weight of Japanese athletes. The subjects in this study were 151 male and female athletes who were Japanese excellent or good runners and swimmers.
Max. Vo₂2 was determined during the maximum running on the treadmill. Treadmill test was made with a constant slope of 8.6%. During the first 2 minutes, the treadmill was set in motion at a certain speed (180 or 200 m/min for male and 160 m/ min for female), and then the speed was increased by 10 m/min every succeeding minute until exhaustion. Expired air during running was collected in Douglas bag every 1 minute upto exhaustion. The sampling gas was analyzed by means of a Beckman oxygen and carbon dioxide analyzer.
The results obtained in this study were as follows ;
1) The regression equations were calculated between max. Vo₂ and body weight in relation to sex and sports (Table 1) .
2) Max. Vo₂ per body weight of the male swimmers ranges from 50 to 70 and that of the male runners is 70 ml/kg/min. For the female swimmers max. Vo₂ is between 40 and 60 and the female runners approximately 60 ml/kg/min.
3) The regression equation was calculated between the mean speed of 5000 m running as performance (Y) and max. Vo₂ per body weight as physical resources (X) for the runners.
Y=0. 0431X+2.50±0.232

The present study was primarily designated as “Chino-Japanese cooperative study on physical fitness of junior track and field athletes” (1989) . The participants were male and female track runners of both countries ranging in age from 13 to 17 years.
Skeletal age and stature for each sex and athletic event for the present series were compared between the two countries. The data of the present series were then compared with the earlier series, that is, the reference data derived from “Chino-Japanese cooperative study on physical fitness of children and youth” (1986) .
Regarding the mean skeletal age of reference data (13 to 17 yrs.), the Japanese are more advanced (0.6 years in boys; 0.5 years in girls) than the Chinese, respectively. On the other hand, for the mean stature, the Chinese are taller (1.92cm in boys; 2.16cm in girls) .
In the present series, the mean differences for skeletal age between the two countries show a tendency to be smaller than those in the reference data (0.38 years for boys and 0.39 years for girls in 100m runners; 0.15 years for boys in 1500m runners and girls in 800m runners), respectively.
Although the mean differences of skeletal age between the two countries are becoming smaller, the stature of the Chinese boys and girls are getting taller than the Japanese (6.9cm in boys and 5.60cm in girls in 100m runners) . The mean differences are not so great as in 100m runners, however, it is 2.50cm in boys of 1500m runners and 4.05cm in girls of 800m runners.
Comparison of the athletic records between the two countries was made and in general little difference was found. The Chinese records are more complete than the Japanese and show statistically significant difference particularly in 17 years old.
In conclusion, the Chinese junior track runners seem to mature later skeletally or biologically than the Japanese, even though they are already taller than the Japanese. As a natural result, more gain in stature and more improvement in the athletic records will be expected for them. Otherwise some differences between the two countries in the process of sampling of the present study could be questioned.