Physical activity and coronary heart disease risk in men - Does the duration of exercise episodes predict risk?

Im. Lee et al., Physical activity and coronary heart disease risk in men - Does the duration of exercise episodes predict risk?, CIRCULATION, 102(9), 2000, pp. 981-986
Citations number
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Journal title
ISSN journal
0009-7322 → ACNP
Year of publication
981 - 986
SICI code
Background-Physical activity is associated with a decreased risk of coronar y heart disease (CHD). However, it is unclear whether the duration of exerc ise episodes is important: Are accumulated shorter sessions as predictive o f decreased risk as longer sessions if the same amount of energy is expende d? Methods and Results-In the Harvard Alumni Health Study, we prospectively fo llowed 7307 Harvard University alumni (mean age 66.1 years) from 1988 throu gh 1993. At baseline, men reported their walking, stair climbing, and parti cipation in sports or recreational activities. For each of the latter activ ities, they also reported the frequency and average duration per episode. D uring follow-up, 482 men developed CHD. In age-adjusted analysis, a longer duration of exercise episodes predicted lower CHD risk (P trend=0.04). Howe ver, after total energy expended on physical activity and potential confoun ders was accounted fur, duration no longer had an independent effect on CHD risk (P trend=0.25); that is, longer sessions of exercise did not have a d ifferent effect on risk compared with shorter sessions, as long as the tota l energy expended was similar. In contrast, higher levels of total energy e xpenditure significantly predicted decreased CHD risk in both age-adjusted (P trend=0.009) and multivariate (P trend=0.046) analyses. Conclusions-These data clearly indicate that physical activity is associate d with decreased CHD risk, Furthermore, they lend some support to recent re commendations that allow for the accumulation of shorter sessions of physic al activity, as opposed to requiring 1 longer, continuous session of exerci se. This may provide some impetus for those sedentary to become more active .