If you want increase your fitness levels, four-minute bursts of high-intensity exercise will do the trick. This is according to a new study, published in the Public Library of Science’s PLoS ONE journal, which found that high-intensity interval training, such as running on a treadmill three times a week, helped overweight participants to give their fitness levels a 10% boost.
General wellness guidelines note that you need to get 150 minutes of moderate exercise or 20 minutes of vigorous exercise a week to stay healthy. However, the findings of the study suggest that you can get the same results from 12 minutes of high-intensity exercise, spread across three sessions. Overweight volunteers who undertook the regime for 10 weeks increased their body’s oxygen uptake (which is a measure of fitness) by 10%, as well as slightly decreasing their blood pressure and glucose levels.
24 men, who were overweight but otherwise healthy, took part in the study. The researchers from the Norwegian University of Science and Technology in Trondheim studied the effects of different exercise regimes on the participants, with half the men the regime taking part in four-minute sessions, three times a week, while the other half completed three 16-minute sessions, each divided into four-minute segments.
In terms of oxygen uptake, both groups demonstrated similar results, with an increase of 10% in the four-minute group, and 13% in the 16-minute group. However, while the blood pressure and glucose levels lowered by similar amounts in both groups, the more intensive 16-minute sessions were more effective at lowering cholesterol and body fat. According to the researchers, ‘These data suggest it may be possible to reduce cardiovascular mortality with substantially less exercise than generally recommended, provided it is performed in a vigorous manner.’
Dr Thomas Lee, Professor of Medicine at Harvard Medical School, commented, ‘Short episodes of very intense exercise can raise one’s risk for a stroke or heart attack or fatal arrhythmia during, or right after, the burst of exertion. I think this approach, which used to be known as “intervals”, is very reasonable and accepted among young athletes … I don’t encourage it among most of my older patients.’
However, Dr Arnt Erik Tjønna said the programme of brief but intensive exercise sessions could be a “time-efficient” method of staying fit, noting, ‘Since we know that more and more people are inactive and overweight, the kind of improvement in physical fitness that we saw in this study may provide a real boost for inactive people who are struggling to find the motivation to exercise.’