Everyone should be doing at least between 20 and 25 minutes of walking a day.
Just 25 minutes of brisk walking a day can add up to seven years to your life, according to health experts.
Researchers have found that moderate exercise could halve the risk of dying from a heart attack for someone in their fifties or sixties.
Coronary heart disease is the UK’s single biggest killer, causing one death every seven seconds, and exercise has long been seen as a way to reduce the risks by cutting obesity and diabetes.
A new study presented at the European Society of Cardiology (ESC) Congress suggested that regular exercise can increase life span.
A group of 69 healthy non-smokers, aged between 30 and 60, who did not take regular exercise were tested as part of the study at Saarland University in Germany.
Blood tests taken during six months of regular aerobic exercise, high-intensity interval training and strength training showed that an anti-aging process had been triggered and helped repair old DNA.
“This suggests that when people exercise regularly, they may be able to retard the process of aging,” said Sanjay Sharma, professor of inherited cardiac diseases in sports cardiology at St George’s University Hospitals NHS Foundation Trust in London.
“We may never avoid be-coming completely old, but we may delay the time we become old. We may look younger when we’re 70 and may live into our nineties.
“Exercise buys you three to seven additional years of life. It is an antidepressant, it improves cognitive function and there is now evidence that it may retard the onset of dementia.”
The advice from experts is that everyone should do at least 20 minutes of walking or jogging a day, given the sedentary lifestyles and changes in diet that have contributed to high death rates from heart disease. Exercise can also improve brain functioning.
Exercise brings benefits at whatever age the person starts. People who start exercising at the age of 70 are less likely to go on to develop a condition that leads to irregular or racing heart rates in 10 per cent of people aged over 80.
“The study brings a bit more understanding of why physical activity has that effect,” said Christi Deaton, Florence Nightingale Foundation Professor of Clinical Nursing Research at Cambridge Institute of Public Health.
“It helps us understand the process of cellular aging, as that’s what drives our organ system and body aging, and the effects physical activity can have on the cellular level.
“The more active you are, and it doesn’t matter when you start, the more benefit you are going to have.”
Heart attacks are mainly triggered by coronary heart disease, which kills around 73,000 people in the UK every year and is the leading cause of death in both sexes. Heart disease generally affects more men than women, although from the age of 50 the chances of developing the condition are similar for both.
According to a separate study, hundreds of young people die every year from “electrical faults” in their otherwise healthy hearts triggered by intense sporting activity.
Sudden cardiac death (SCD) is a rare occurrence that affects one in 50,000 athletes, although most who die are men, researchers found. In the 35 year history of the London Marathon, only one woman has died compared to 13 men.
The study’s authors, from St George’s University Hospital in London, found that a large proportion of cases of SCD in sport occurred in people with anatomically normal hearts, but with inherited faults in the heart’s electrical system that causes them to miss beats and trigger death.