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ECG aberrations, latent coronary heart disease and cardiopulmonary fitness in various age groups of Norwegian cross-country skiers.

To assess the prevalence of possible, latent coronary heart disease (CHD) among physically active men, 149 elite cross-country skiers in three age groups (26-33, 43-50 and 58-64 years) were invited for an examination which included clinical examination, Vitalogram, resting ECG, and a near maximal bicycle test. Of the invited men, 122 participated, i.e. 81.8%. The following findings were made: Normal clinical findings in all except 2, low resting heart rate, lung function parameters of about normal mean; voltage signs of left ventricular hypertrophy in resting ECG in 61/122, incomplete right bundle branch block in 14/122, codable Q waves (Minnesota Code, MC) in 5/87 from the highest age groups, ischaemic exercise ECG changes of MC 4.1 or 4.2 types in 11/87 vs. 1/35 in the two oldest vs. the youngest age group. Physical performance was very high in all age groups, but regular training did not seem to inhibit the normal age-dependent decline in physical performance. The resting and exercise ECG data in the two oldest age groups did not differ favourably from similar data obtained in sedentary men of the same age from approximately the same geophraphic area. Thus, it is possible that regular strenuous exercise and training may not protect against the development of CHD. The implications of such a view are briefly discussed.