Intensity versus duration of cycling, impact on all-cause and coronary heart disease mortality: the Copenhagen City Heart Study

Background: Current recommendations prescribe that every adult should accumulate 30 minutes or more of moderate physical activity in leisure time, preferably every day of the week. The optimal intensity, duration, and frequency still have to be established. The aim of this study was to examine the impact of intensity versus duration of cycling on all-cause and coronary heart disease mortality. Design: Relative intensity and duration of cycling were recorded in 5106 apparently healthy men and women aged 21-90 years drawn from the general population of Copenhagen, and followed for an average of 18 years. Total number of deaths during follow-up was 1172, of these 146 were coronary heart disease deaths. For both sexes we found a significant inverse association between cycling intensity and risk of all-cause and coronary heart disease death, but only a weak association with cycling duration. The difference in expected lifetime in relation to intensity of cycling was calculated. Men with fast intensity cycling survived 5.3 years longer, and men with average intensity 2.9 years longer than men with slow cycling intensity. For women the figures were 3.9 and 2.2 years longer, respectively. Conclusion: Our findings indicate that the relative intensity, and not the duration of cycling, is of more importance in relation to all-cause and coronary heart disease mortality. Thus our general recommendations to all adults would be that brisk cycling is preferable to slow.