By Rebecca Knight
Finally, some health news I can get behind: it’s possible to get more fit by doing less exercise.
A study, conducted by researchers at McMaster University in Canada, finds that brief spurts of high-intensity interval training – a form of exercise with the accurate acronym: HIT – produces the same benefits to your body as conventional long duration endurance training. (HIT means doing a number of short bursts of concentrated exercise with short recovery breaks in between.)
“Doing 10 one-minute sprints on a standard stationary bike with about one minute of rest in between, three times a week, works as well in improving muscle as many hours of conventional long-term biking less strenuously,” says Prof Martin Gibala, one of the authors of the research.
To achieve the study’s equivalent results by endurance training you’d need to do – get this – over 10 hours of continuous moderate bicycling exercise over a two-week period. Here is a link to the abstract of the study, which is published in the Journal of Physiology:
In a previous study, Gibala and his colleagues showed that HIT in young healthy university students is as effective as traditional endurance training despite the fact that HIT is much less exercise, and takes much less time.
That prior study, however, used a rather extreme set-up that involved “all out” pedaling on a specialised laboratory bicycle. The new study used a standard stationary bicycle and a workload which was above most people’s comfort zone -about 95 per cent of maximal heart rate – but only about half of what can be achieved when people sprint at an all-out pace.
It’s well established that repeated moderate long-term exercise increases oxygen delivery to muscles and helps in the removal of waste products. Exercise also improves the way muscles use the oxygen to burn the fuel in mitochondria, known as “cellular power plants.”
Cycling or running for hours a week expands the network of vessels supplying muscle cells and also heightens the numbers of mitochondria in them so that a person can carry out activities of daily life more effectively and without strain, and with less risk of a heart attack, stroke or diabetes.
Just why HIT is so effective remains unclear, say the McMaster researchers. However, it appears that HIT stimulates many of the same cellular pathways that are responsible for the benefits we associate with endurance training.
Of course there is one big downside to this news: saying you’re “too busy” to go to the gym is no longer a good excuse. Who me?
Margaret McCartney
Clive Cookson
Andrew Jack