HABITUAL PHYSICAL ACTIVITY AND MYOCARDIAL INFARCTION

The authors present some data, drawn from personal epidemiological investigations, concerning a possible relationship between habitual physical activity at work and the development of myocardial infarction (MI). An occupational group of middle-aged Italian Railroad employees has shown that men with sedentary or light occupations seem to have higher mean levels of the biological parameters considered as coronary risk factors. Another study in the whole population of the Italian Railroad employees indicates that people with sedentary or moderately active jobs suffer a higher mortality from MI than their contemporaries engaged in heavy work. A study of the prevalence of MI defined from some ECG criteria, conducted in four groups of middle-aged men with different percentages — in each group — of people engaged in various levels of physical activity, showed a definitely higher rate of the disease in the group with 100% of the men engaged in sedentary jobs as compared with the other three groups where sedentary people were represented by 6 to 21% of the total. The 5-year incidence figures for MI observed in two of the four groups of the previous study confirmed a higher, even though not significant, rate of MI in sedentary and moderately active people than in heavy workers. In spite of the evidence of some of the above data the authors are very cautious in drawing definite conclusions on the relationship between physical activity and development of myocardial infarction. © 1969 S. Karger AG, Basel.