The electrocardiographic findings in more than 20, 000 athletes are studied.
I. Resting electrocardiograms (ECG) of 10, 149 high school athletes are analysed. Abnormal ECG are encountered in 12.45%. Following findings are found: Right bundle branch block (RBBB) (4.03%), Left ventricular hypertrophy (2.89%), Premature beats (1.09%), A-V block (0.86%), Right ventricular hypertrophy (0.85%) . RBBB are further analysed and divided into 4 types from the QRS pattern in V1. The frequent RBBB in young athletes is confirmed and its significance is also discussed.
II. T wave abnormalities are observed in 5 cases of resting ECGs of all this sample. Essential abnormalities are T wave inversion simulating myocardial infarction in limbs leads (usually in II, III, aVF) and precordial leads and concomitant slight elevation in precordial leads.
Physical and laboratory examinations in 5 cases disclose no evidence of organic heart disease. In 4 of 5 cases, exercise ECGs are revealed the normalisation-tendency of the T wave change. A brief discussion concerning the possible mechanisms of these changes are made.
III. ECGs of middle and old age athletes are also observed at rest and after the long distance running. The distance are different in each age-group, but all of them run at least more than 5 km. The 409 resting ECGs are taken before the running game and the 201 post running tracing are obtained as soon as possible after the game.
At rest, ECG findings suggestive of coronary insufficiency are detected in 4 of 108 samples of sixties group and in 1 of 25 samples of seventies group.
Ischemic electrocardiographic responses after the running game are found as follow: 3/51 (5.8%) of fourties group, 9/59 (15.1%) of fifties group, 20/70 (28.6%) of sixties group and 6/21 (28.6%) of over seventies group.
Arrhythmias are not so frequently observed in each group. These ischemic re-sponses suggest that medical check-up especially cardiovascular evaluation is necessary in middle and old age athletes to prevent accidents on sports.

This time the statistics for injuries and disorders due to sports in the five-year period up to 1985 were taken, evaluated and compared with those of the last five-year period. The following results were obtained :
1. There were 1, 300 cases of injuries and disorders due to sports in the five-year period up to 1985, which was 4.4% of the total number of outpatients in the department of orthopaedics.
2. Sex : There were more male patients, but the rate of female patients has been increasing lately.
3. Age : Patients in their teens or twenties accounted for about 70%.
4. Body Side : There was no significant difference between incidence of injury on the right side of body or the left, but cases of injuries on both sides have been increasing recently.
5. Kind of Sport : The largest number of trauma were due to skiing, although the number of trauma resulting from playing tennis has been high in the past five-years of investigation.
6. Time of Injury ; Most patients were injured during practice, followed by recreation and game.
7. Position of Truma : Most cases were injuries to their knee joints from skiing.

This time the statistics for injuries and disorders due to sports in the five-year period up to 1985 were taken, evaluated and compared with those of the last five-year period. The following results were obtained :
1. There were 1, 300 cases of injuries and disorders due to sports in the five-year period up to 1985, which was 4.4% of the total number of outpatients in the department of orthopaedics.
2. Sex : There were more male patients, but the rate of female patients has been increasing lately.
3. Age : Patients in their teens or twenties accounted for about 70%.
4. Body Side : There was no significant difference between incidence of injury on the right side of body or the left, but cases of injuries on both sides have been increasing recently.
5. Kind of Sport : The largest number of trauma were due to skiing, although the number of trauma resulting from playing tennis has been high in the past five-years of investigation.
6. Time of Injury ; Most patients were injured during practice, followed by recreation and game.
7. Position of Truma : Most cases were injuries to their knee joints from skiing.