Jogging adds five years to your life

Back in the 1970s, many people believed that jogging was a health hazard. This belief prompted Danish researchers to set up an extensive research project which has now been completed. The conclusion is clear: we extend our lives by jogging. (Photo: Colourbox)

Regular jogging could add more than five years to your life expectancy.

This is the startling result of a comprehensive study, based on figures for Copenhageners’ life expectancy. The findings have not yet been published in a scientific journal, but they have just been presented at the EuroPRevent2012 in Dublin.

“Our study shows that men increase their life expectancy by an average of 6.2 years if they jog, and women by 5.6 years,” says the man behind the research project, MD Peter Schnohr, a senior researcher at Bispebjerg Hospital in Copenhagen.

Studied Danes for 35 years

The findings are based on the Copenhagen City Heart Study – a comprehensive population study, which has so far resulted in more than 700 scientific articles about health.

The study was started back in 1976, when Danish health researchers decided to learn more about heart disease in the Danish population.

Jogging was once thought to be a killer

Schnohr was one of the doctors who launched the project. Back in 1969, he helped organise the first ‘Eremitageløb’, a popular annual fun run in Copenhagen. This inaugural run made the headlines because a 46-year-old man collapsed with heart problems and died.

This was the beginning of a long series of newspaper articles about how the new jogging craze could kill middle-aged men.

The older you are, the more you get out of exercising. But middle-aged men should be careful not to overexert themselves when jogging. They should strive to feel just a little breathless during their jogging, not too much. (Photo: Colourbox)

The 1970s saw a steady stream of stories from the US about middle-aged joggers falling dead in the middle of a run.

“That left us wondering: is this dangerous?” says Schnohr.

“That’s why we focused on jogging from the very start. Today – 35 years later – we can finally conclude that jogging is not dangerous. On the contrary, it is beneficial.”

Joggers are 44 percent less likely to die

Some 20,000 people, aged between 20 and 93, took part in the Copenhagen City Heart Study.

• All participants were asked regularly about their exercise and running habits. They were asked to state how much time they spent on jogging per week and also to evaluate their running pace – slow, medium or fast.
• It turned out that out of the 20,000 locals, 1,878 jogged at a fast pace – 1,116 men and 762 women.
• Over the past 35 years since the study began, 10,158 of those who did not jog died. For the joggers, the number was 122.

Based on these figures, taking account of differences such as age, smoking habits, blood pressure and cholesterol, the researchers calculated that the risk of dying in the 35-year period was 44 percent lower for those who were in the habit of jogging – and that applied to men and women alike.

Unhealthy to overdo the jogging

Schnohr adds, however, that it can be a bad idea to jog too much. The figures from the study indicate that people who do a lot of jogging actually tend to die as early as those who don’t engage in jogging at all.

”It’s common sense to try and recover between the runs,” he says. “Old people, in particular, should avoid running more than two times a week.”

He offers a conservative estimate of how much jogging is directly healthy:

”I would say a total of 1-2.5 hours per week, spread over no more than three runs. The important thing is that the jogging leaves you short of breath.”

Although the figures have yet to be finalised, they reveal a clear tendency:

“Not exercising at all is bad for you, and so is doing too much of it. And that applies to both cycling, walking and jogging.”

Jogging becomes more effective with age

The study doesn’t say anything specific about how many years you need to keep up the jogging in order to prolong your life.

”We actually don’t know. But I believe the beneficial effects come quickly. We know that a 70-year-old gains 2-3 years by taking up cycling. I usually say that the older you are, the more you get out of your workout.”

Sick people competed in the ‘70s

This study claims to have busted the myth that jogging shortens life expectancy. But what was it then that caused all the deaths among joggers in the ‘70s?

”People didn’t know much about heart disease back then, so people signed up for the runs, even though they may have been sick,” says Schnohr.

“Today people know more. But there are still those who are unaware that they have a severe heart disease.”

He says that for people over the age of 40, even a slow jog can be hard work, so it’s important not to overdo it.

An article with the latest findings from the Copenhagen City Heart Study has been submitted to an internationally acclaimed American medical journal.

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Read this article in Danish at Videnskab.dk