A small preliminary study suggests doing one minute of intense exercise several times a week boosts fitness in older people.
A study in 12 older people showed that high intensity training (HIT) – repeated cycles of short bursts of all-out physical exertion followed by a minute or two of rest – improved their fitness and certain measures of their health.
HIT exercises has become popular in recent years, with researchers and gyms claiming that people can dramatically improve their fitness with a few minutes work a week. But its benefits have not been tested in older people.
The study, by researchers at Abertay University in Dundee, included 12 people with an average age of 65. Half of the group followed a HIT program twice a week for six weeks. Each session involved six bursts of cycling flat-out for six seconds, followed by one minute of rest.
Over six weeks the HIT cycles were lengthened until the people were cycling for six 10-second bursts – or one minute in total – with rest periods in between each burst.
Those who followed the HIT program had lower blood pressure and used more oxygen while exercising than at the start of the study: both signs of good health and better fitness. They also found everyday physical activity, like getting out of a chairs and walking, easier.
The researchers said the results point to a way to improve older people's health.
Researcher Dr John Babraj told the BBC: "We've got an ageing population and if we don't encourage them to be active, the economic burden of that is going to be astronomical.
"A lot of diseases are associated with sedentary behaviour – like cardiovascular disease and diabetes – but if we can keep people active and functioning then we can reduce the risk.
Dr Adam Gordon, a consultant and honorary secretary of the British Geriatrics Society, told the BBC: "This is a brilliant, fantastic piece of work challenging assumptions about what the right type of exercise is in old age, but I'd encourage them to investigate the benefits in even older and even more frail people.
"The broad message is that you're never too old, too frail, too ill to benefit from exercise, as long as it's carefully chosen. Even into your 80s and 90s there's a benefit from developing a very slight sweat by exercising on multiple occasions per week."
Dr Babraj's group plan larger trials to confirm their early findings. He stressed people considering HIT should check with their doctor first. Although the periods of exercise in HIT are short, they should be intense to get the most benefit. So HIT may not be safe for people with heart problems, for example.
The research is published in the Journal of the American Geriatric Society.