Jogging for as little as an hour a week can put years on your life, new research has shown.
Regular running increases the average life expectancy of men and women by around six years, a study found.
The greatest benefit came from jogging at a "slow or average" pace - enough to cause slight breathlessness - rather than pushing to physical limits.
Danish heart expert Dr Peter Schnohr, who led the study of almost 2,000 male and female joggers, said: "The results of our research allow us to definitively answer the question of whether jogging is good for your health.
"We can say with certainty that regular jogging increases longevity. The good news is that you don't actually need to do that much to reap the benefits."
The jogging research is part of the Copenhagen City Heart Study which has been monitoring the health of 20,000 Danish men and women aged 20 to 93 since 1976.
A team led by Dr Schnohr looked at death rates among a sub-group of 1,116 male and 762 female joggers over a period of up to 35 years.
Participants were asked how much time they spent jogging each week, and whether they ran at a slow, average or fast pace.
Compared with non-joggers in the main heart study population, the risk of death for both male and female runners was reduced by 44%.
The data showed that, after taking account of age, jogging increased the lifespan of men by 6.2 years and of women by 5.6 years.
Further analysis of the association between jogging and death rate revealed a "U-shaped curve".
This meant improvements were seen with increasing levels of exercise until an optimum point was reached, after which they reduced.
Between one hour and two-and-a-half hours of moderately paced jogging a week, undertaken over two to three sessions, was ideal, said the scientists.
"The relationship appears much like alcohol intakes," said Dr Schnohr, who presented the findings today at a meeting of heart experts in Dublin. "Mortality is lower in people reporting moderate jogging than in non-joggers or those undertaking extreme levels of exercise.
"You should aim to feel a little breathless, but not very breathless."
He said jogging delivered multiple health benefits, including raised oxygen uptake, increased insulin sensitivity, higher levels of "good" HDL cholesterol, lowered blood pressure, and reduced blood clotting.
Regular running also improved heart and immune function, bone density while reducing inflammation, and protection against obesity. Jogging first became popular in the 1970s when middle-aged men started running to reduce their risk of heart attacks and strokes.
Since then there has been an ongoing debate about whether, on balance, jogging is beneficial or harmful.
"After a few men died while out on a run, various newspapers suggested that jogging might be too strenuous for ordinary middle-aged people," said Dr Schnohr.
Dr Schnohr, from Bispebjerg University Hospital, led another study reported last year which showed that cycling can increase lifespan by five years.
But in this case it was "fast pedallers" who did the most intense exercise who benefited most.
The EuroPRevent2012 meeting, taking place in Dublin over the next two days, is organised by the European Association for Cardiovascular Prevention and Rehabilitation.
Natasha Stewart, senior cardiac nurse at the British Heart Foundation, said: "Physical activity has long been associated with improved health and so it's no surprise to see just how beneficial jogging could be.
"Staying active can help prevent and manage a wide variety of health conditions and keep your heart in great shape. It can help the way you look and feel today but could also help to protect your heart health in the future too.
"Jogging might not be for everybody but there are plenty of other ways to keep active. Swimming, walking or even a spot of gardening can be beneficial, too. If you have concerns about the impact of exercise on your health, visit your GP first."
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