High-mileage, high-intensity joggers die at the same rate as those who do not jog. In other words, jogging light is best for health. This is the conclusion of a recent paper in the Journal of the American College of Cardiology. Specifically, it says that light and moderate joggers have lower rate death rates than people who do not jog and considered sedentary. But, significantly, joggers classified as “strenuous” have a “mortality rate not statistically different” from sedentary people.

The study began with an acknowledgment long held in research that physically active people have a minimum 30 percent lower risk of death than those who are inactive. What it hoped to determine, however, is the ideal quantity of exercise that improves longevity.

A suggestion posed by the paper is that a point exists at which physical exertion actually becomes detrimental. Although the study did not identify why strenuous jogging can harm people, the researchers did note that intense exercise puts stress on the cardiovascular system. The hypothesis is that, over time, the heart can be damaged by strenuous jogging.

The lead author of Dose of Jogging and Long-Term Mortality is Dr. Peter Schnohr. He said excessive exercise over a long period may be associated with diastolic dysfunction, coronary artery calcification and stiffening of the walls of large arteries.

The study examined the data collected in the The Copenhagen City Heart Study, a long-term look at the cardiovascular health of over 5,000 people. For the Dose of Jogging study, Schnohr and his team examined the data acquired from over 4,000 healthy but inactive non-joggers and almost 1,100 healthy joggers over 12 years.

For purposes of the study, strenuous joggers were identified as people who jogged faster than seven miles per hour more than four hours each week or those who jogged faster than seven miles per hour more than 2 1/2 hours each week and more than three times each week. Excluded from the examination were people diagnosed with stroke, heart disease or diabetes.

In the end, a conclusion: The amount of jogging found best for reducing mortality was one to 1.4 hours each week, but with no more than three days per week, “at a slow or average pace.” Such an “average” pace was defined as five miles per hour, or a 12-minute mile. On the other hand, those who jogged between one hour and 2.4 hours each week had 71 percent lower risk of dying was 71 percent lower than those who didn’t exercise at all.