It's never too late to start exercising, according to a major study which found active over-60s cut their risk of heart attack and stroke.
People who went from being sedentary to working out three or four times a week reduced their risk of heart problems by up to 11 per cent compared to those who didn't exercise.
And the level of activity needed to cause a change was equal to just one hour of running per week – less than the 75 to 150 minutes recommended by the NHS.
The study of more than a million people found those who used to work out five times a week but stopped saw their risk rise by 27 per cent.
The researchers in South Korea said their findings were evident even in people with disabilities and chronic conditions such as high blood pressure or type 2 diabetes.
They have urged doctors to prescribe physical activity for older patients in a bid to prevent major health problems.
It's never too late to start exercising, according to a major study which found over-60s who became more active cut their risk of heart attack and stroke
Kyuwoong Kim, a PhD student at Seoul National University said: 'The most important message from this research is that older adults should increase or maintain their exercise frequency to prevent cardiovascular disease.
'While older adults find it difficult to engage in regular physical activity as they age, our research suggests that it is necessary.
'We believe that community-based programmes to encourage physical activity among older adults should be promoted by governments.
'Also, from a clinical perspective, physicians should "prescribe" physical activity along with other recommended medical treatments for people with a high risk of cardiovascular disease.'
Physical activity is well established as a means of preventing heart disease, but it's not clear if the benefits remain when exercise level changes.
The study looked at 1,119,925 men and women aged 60 years or older.
Exercise burns calories which can maintain a healthy weight. Obesity is one of the biggest causes of heart problems.
It lowers blood pressure, cholesterol, and helps regulate blood sugar levels, all of which have been linked to cardiovascular disease.
A single bout of exercise may protect your heart immediately through a process known as ischemic preconditioning. A little bit of ischemia — defined as an inadequate blood supply to part of the body, especially the heart — may be a good thing.
It allows the heart to adapt and protect itself from longer episodes of ischemia, which normally occurs from a blockage in arteries.
Source: Harvard Medical School
They underwent two health checks by the Korean National Health Insurance Service in 2009-2010 and again in 2011-2012.
At each check, the participants' levels of moderate and