Cardiovascular studies on former endurance athletes

Abstract

1. 1. Sixty-one former champion endurance runners or cross-country skiers, 40 to 79 years of age, were submitted to a thorough evaluation of the cardiovascular system. In addition, the study program included a series of anthropometric measurements and a number of laboratory tests. A control group of 54 nonathletes of the same age was submitted to similar studies. The control group consisted of men in sedentary or semisedentary occupations. 2. 2. The former athletes differed from the controls by being shorter, having a smaller sitting height and a smaller body weight, but a larger wrist breadth. There was no difference in ponderal index, knee breadth, biacromial breadth, bicristal breadth, or in the ratio of the two latter measures. 3. 3. Both the mean systolic and diastolic blood pressures of the athletes ( 137 87 mm. Hg ) were significantly lower than those of the controls ( 147 92 mm. Hg ). 4. 4. There was no difference in the serum cholesterol level or in the hemoglobin concentration of the blood between the two groups. 5. 5. Coronary heart disease was diagnosed in 17 of the 54 controls and in 15 of the 61 athletes. Eight control subjects, but only 2 athletes, had had symptoms of coronary disease. 6. 6. The current physical activity was greater in the athletes than in the controls. 7. 7. There were fewer nonsmokers and more heavy smokers, as well as exsmokers, in the control group than in the group of athletes. 8. 8. Among men aged from 40 to 69, the electrocardiogram, by Minnesota Code, showed in 5 of 49 controls and in 1 of 55 athletes Q or QS patterns indicative of old myocardial infarction (I 1–3); S-T segment depression at rest (IV 1–3), or after submaximal exercise (XI 1–3) in 12 of 49 controls and in 8 of 55 athletes; flat or negative T waves at rest or after exercise (v 1–3, XII 1–3) in 6 of 49 controls and in 4 of 55 athletes. High amplitude R waves (III 1) occurred in 6 of 49 controls and in 8 of 55 athletes aged from 40 to 69. In the athletes, high R waves were associated with high level of physical activity (6 of 8) rather than with hypertension (1 of 8); in the controls the association was intimate with hypertension (5 of 6) and loose with physical activity (1 of 6). 9. 9. Twenty-nine of the controls and 38 of the athletes were considered as “healthy” subgroups. The subscapular skinfold of healthy athletes was thinner than that of the controls, whereas there was no significant difference in the upper arm skinfold thickness. As regards the other anthropometric measurements, the comparison of healthy subgroups did not show any essential differences from those revealed by the comparison of the total groups. The systolic blood pressure was lower in healthy athletes than in the controls. 10. 10. Healthy athletes had a larger maximal QRS vector, a larger roentgenologic heart volume, a lower heart rate during exercise, and consequently a higher calculated maximal oxygen uptake, than the controls. 11. 11. The maximal QRS vector showed a statistically significant positive correlation with heart volume in healthy controls but not in healthy athletes. The lack of correlation between these two parameters is considered to suggest that dilatation rather than hypertrophy is the main determinant of the increased heart volume induced by training. 12. 12. The prevalence of electrocardiographic abnormalities in former champion endurance athletes is compared with that observed in other series. “Ischemic” changes occur with the same frequency in former athletes and the general population. However, severe manifestations and subjective symptoms of coronary heart disease may be rarer among athletes.