The rise in popularity of activity trackers like the Fitbit has left many convinced that racking up their daily 10,000 steps is a sure-fire route to staying in shape.
But experts have now argued that fitting in just a couple of minutes of exercise each week is in fact more beneficial than getting those steps in.
Writing in The Times, Dr Michael Mosley revealed that introducing just three, 40 second sessions of high intensity exercise each week can actually have more of an impact on your health than the much talked-about 10,000 step target.
In fact, researchers on the upcoming BBC show The Truth About Getting Fit found that just two minutes of HIIT (high-intensity interval training) per week could reduce the risk of developing heart disease by as much as 20 per cent.
High intensity work outs, such as quick burst star jumps or 40 seconds on an exercise bike, could be more beneficial to the body than 10,000 steps. Pictured: Dr Michael Mosley practises HIIT in new BBC documentary The Truth About Getting Fit
In an experiment conducted with Sheffield Hallam University, the diet expert asked a group of volunteers to walk 10,000 steps a day and another group to do three brisk ten-minute walks a day.
They found that while those who had to reach the steps goal struggled, the brisk walkers’ fitness levels improved more – a result Dr Mosley puts down to doing specifically vigorous activity, rather than just walking to meet a goal.
In The Truth About Getting Fit, Dr Mosley also tests the effectiveness of HIIT, by asking volunteers to cycle for 40 seconds three times a week.
Dr Niels Vollaard, a lecturer in health and exercise science at the University of Sterling, explains how during the first 20 seconds of activity the body breaks down glycogen, a form of sugar stored in the muscles, and triggers the release of ‘signalling molecules’.
In the next 20 seconds these molecules are activated, and help stimulate the growth of other muscles, such as the heart muscle.
A group of volunteers had their their maximum oxygen uptake (VO2 max) assessed before and after completing three vigorous, 40 second cycles a week for five weeks
Fitbit fans aim to rack up 10,000 steps each day in an effort to keep fit and stay in shape
Putting this to the test, the show put an exercise bike in a busy London office and asked six volunteers to complete the 40 second regimen three times a week for five weeks.
Their maximum oxygen uptake (VO2 max) – which gives an indication of how strong a person’s lungs and heart are, and how fit they are for their age – was measured both before and after the experiment.
The results showed the volunteers had improved their fitness levels by an average 11 per cent
Dr Michael Mosley emphasises the importance of strenuous physical activity – even if only in short bursts – in the BBC show
When the experiment came to an end after five weeks the group – most of whom had managed to keep up their thrice-weekly routine – saw an overall improvement in their fitness levels of 11 per cent, with the highest recorded being 14 per cent.
If the group kept up the regimen beyond the experiment, the show’s experts said, an 11 per cent increase in fitness could result in a 20 per cent reduction to their risk of developing heart disease.
According to Dr Vallaard, the short bursts of high intensity activity have the same effect as a 45 minute run at a steady pace three times a week.
The Truth About Getting Fit airs on Wednesday night at 8pm on BBC One