Scientists tracked the progress of 1,098 healthy joggers and 413 healthy but sedentary non-joggers for 12 years. They found heavy-duty joggers were as likely to die as inactive non-joggers, while “light” joggers had the lowest death rates.
Jogging from one to 2.4 hours a week was associated with the lowest mortality and the “optimal” jogging frequency was no more than three times per week.
Overall, significantly lower mortality rates were found in those who adopted a slow or moderate jogging pace.
Researchers registered 28 deaths among joggers and 128 among inactive non-joggers. In general, joggers were younger, had a lower blood pressure and body mass index, and were less likely to smoke or suffer from diabetes.
Lead scientist Dr Peter Schnohr, of Frederiksberg Hospital in Copenhagen said: “It is important to emphasise that the pace of the slow joggers corresponds to vigorous exercise and strenuous jogging corresponds to very vigorous exercise.
“When performed for decades, this activity level could pose health risks, especially to the cardiovascular system. The U-shaped association between jogging and mortality suggests there may be an upper limit for exercise dosing that is optimal for health benefits.
“If your goal is to decrease risk of death and improve life expectancy, jogging a few times a week at a moderate pace is a good strategy.
“Anything more is not just unnecessary, it may be harmful.”
The findings are published in the Journal of the American College of Cardiology.