Walking, swimming and running could help middle-aged couch potatoes reverse their risk of heart failure, a study suggests.
Decades of damage caused by leading a sedentary lifestyle could be reversed over two years with the “right dose” of exercise, researchers found.
They said they had discovered an exercise regimen which should be a “prescription for life”, which people should incorporate into their daily lives.
The study, published in the American Heart Association’s journal Circulation, examined the hearts of 53 adults aged 45 to 64 who were healthy but sedentary at the start of the study.
People who sit for long periods of time are deemed to lead a sedentary lifestyle, which can increase the risk of the heart muscle shrinking and stiffening in late-middle age and increases heart failure risk.
Participants were divided into two groups and either received two years of training, including high and moderate-intensity aerobic exercise four or more days a week, or the control group, which participated in regular yoga, balance training and weight training three times a week for two years.
The team, led by experts from the Institute for Exercise and Environmental Medicine in Texas, in the US, found that over two years the exercise group significantly decreased cardiac stiffness and shown improvements in how the body uses oxygen.
Lead author Benjamin Levine, director of the institute, said: “The key to a healthier heart in middle age is the right dose of exercise, at the right time in life.
“We found what we believe to be the optimal dose of the right kind of exercise, which is four to five times a week, and the ‘sweet spot’ in time, when the heart risk from a lifetime of sedentary behaviour can be improved – which is late-middle age.
“The result was a reversal of decades of a sedentary lifestyle on the heart for most of the study participants.”
He added: “We found that exercising only two or three times a week didn’t do much to protect the heart against ageing.
“But committed exercise four to five times a week was almost as effective at preventing sedentary heart ageing as the more extreme exercise of elite athletes.
“We’ve also found that the ‘sweet spot’ in life to get off the couch and start exercising is in late-middle age, when the heart still has plasticity.”
The recommended exercise regime includes at least one long session a week – such as an hour of tennis, cycling, running, dancing, brisk walking; one high-intensity aerobic session; two or three days a week of moderate intensity exercise – where exercisers break a sweat but can still carry on a conversation, and at least one weekly strength training session.
Levine added: “Based on a series of studies performed by our team over the past five years, this ‘dose’ of exercise has become my prescription for life.
“I think people should be able to do this as part of their personal hygiene – just like brushing your teeth and taking a shower.”