No "lack of time" excuse for exercise according to study

A Journal of Physiology study adds to the growing evidence for the benefits of short term high-intensity interval training (HIT) as a time-efficient but safe alternative to traditional types of moderate long term exercise. Astonishingly, it is possible to get more by doing less. "We have shown that interval training does not have to be 'all out' in order to be effective," says researchers. "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." HIT means doing a number of short bursts of intense exercise with short recovery breaks in between.

The new study used a standard stationary bicycle and a workload which was still above most people's comfort zone -about 95% of maximal heart rate -- but only about half of what can be achieved when people sprint at an all-out pace. This less extreme HIT method may work well for people (the older, less fit, and slightly overweight among us) whose doctors might have worries about them exercising "all-out." We have known for years that repeated moderate long-term exercise tunes up fuel and oxygen delivery to muscles and aids the removal of waste products. Exercise also improves the way muscles use the oxygen to burn the fuel in mitochondria, the microscopic power station of cells. Running or cycling for hours a week widens the network of vessels supplying muscle cells and also boosts the numbers of mitochondria in them so that a person can carry out activities of daily living more effectively and without strain, and crucially with less risk of a heart attack, stroke or diabetes.

But the traditional approach to exercise is time consuming. This research shows that the same results can be obtained in far less time with brief spurts of higher-intensity exercise. To achieve the study's equivalent results by endurance training you'd need to complete over 10 hours of continuous moderate bicycling exercise over a two-week period.

Steve - very good to know for those of us are time crunched!