Dose of Jogging and Long-Term Mortality The Copenhagen City Heart Study
Peter Schnohr et al.
J Am Coll Cardiol. 2015;65(5):411-419.
Abstract
Background People who are physically active have at least a 30% lower risk of death during follow-up compared with those who are inactive. However, the ideal dose of exercise for improving longevity is uncertain.
Objectives The aim of this study was to investigate the association between jogging and long-term, all-cause mortality by focusing specifically on the effects of pace, quantity, and frequency of jogging.
Methods As part of the Copenhagen City Heart Study, 1,098 healthy joggers and 3,950 healthy nonjoggers have been prospectively followed up since 2001. Cox proportional hazards regression analysis was performed with age as the underlying time scale and delayed entry.
Results Compared with sedentary nonjoggers, 1 to 2.4 h of jogging per week was associated with the lowest mortality (multivariable hazard ratio [HR]: 0.29; 95% confidence interval [CI]: 0.11 to 0.80). The optimal frequency of jogging was 2 to 3 times per week (HR: 0.32; 95% CI: 0.15 to 0.69) or ≤1 time per week (HR: 0.29; 95% CI: 0.12 to 0.72). The optimal pace was slow (HR: 0.51; 95% CI: 0.24 to 1.10) or average (HR: 0.38; 95% CI: 0.22 to 0.66). The joggers were divided into light, moderate, and strenuous joggers. The lowest HR for mortality was found in light joggers (HR: 0.22; 95% CI: 0.10 to 0.47), followed by moderate joggers (HR: 0.66; 95% CI: 0.32 to 1.38) and strenuous joggers (HR: 1.97; 95% CI: 0.48 to 8.14).
Conclusions The findings suggest a U-shaped association between all-cause mortality and dose of jogging as calibrated by pace, quantity, and frequency of jogging. Light and moderate joggers have lower mortality than sedentary nonjoggers, whereas strenuous joggers have a mortality rate not statistically different from that of the sedentary group.
Perspectives
COMPETENCY IN MEDICAL KNOWLEDGE: Compared with more sedentary people, people who jog regularly exhibit a significantly lower all-cause mortality rate. Those who jog lightly or moderately appear to benefit more than strenuous joggers, whose long-term mortality rate is similar to that of sedentary people.
COMPETENCY IN PATIENT CARE: When prescribing exercise to improve longevity, strenuous exercise is not necessary and might reduce the health benefits of light to moderate physical activity.
TRANSLATIONAL OUTLOOK: Further studies are needed to explore the mechanisms by which excessively strenuous exercise adversely affects longevity before the pattern of association between exercise intensity and long-term mortality can be incorporated into physical activity recommendations for the general public.
