Can three minutes of exercise a week help make you fit?

Michael Mosley on exercise bike

A few relatively short bursts of intense exercise, amounting to only a few minutes a week, can deliver many of the health and fitness benefits of hours of conventional exercise, according to new research, says Dr Michael Mosley. But how much benefit you get from either may well depend on your genes.

When I first read studies which suggested that I could make significant and measurable changes to my fitness by doing just three minutes of exercise a week, I was incredulous.

But this apparently outrageous claim is supported by many years of research done in a number of different countries including the UK, so I decided to give it a go.

Start Quote

Aerobic fitness is a measure of how good your heart and lungs are at getting oxygen into your body and is an excellent predictor of future health”

End Quote

My guide into the world of High Intensity Training (HIT), was Jamie Timmons, professor of ageing biology at Birmingham University.

Jamie assured me that by doing just three minutes of HIT a week for four weeks, I could expect to see significant changes in a number of important health indices.

The first, and the one I was most interested in, is insulin sensitivity. Insulin removes sugar from the blood, it controls fat and when it becomes ineffective you become diabetic.

My father was a diabetic and died from complications of that disease. Jamie assured me that research from a number of centres has shown that three minutes of HIT a week improves insulin sensitivity by an average of 24%.

The second improvement I was likely to see would be in my aerobic fitness. Aerobic fitness is a measure of how good your heart and lungs are at getting oxygen into your body and is an excellent predictor of future health. I asked Jamie why.

"The simple answer is we don't know," he replied. "What we do know is that it is a very, very powerful predictor of future health."

Genetic test

So if I could improve my insulin sensitivity and my aerobic fitness then that should improve my general health. But Jamie said there was a potential sting in the tail. There was a possibility that I wouldn't improve. Not because HIT doesn't work but because I've inherited the wrong genes.


Michael Mosley
  • Michael Mosley presents Horizon: The Truth About Exercise on BBC Two at 21:00 GMT on Tuesday 28 February 2012 or watch online via iplayer (UK only) afterwards at the above link

The fact is that people respond to exercise in very different ways. In one international study 1,000 people were asked to exercise four hours a week for 20 weeks. Their aerobic fitness was measured before and after starting this regime and the results were striking.

Although 15% of people made huge strides (so-called "super-responders"), 20% showed no real improvement at all ("non-responders").

There is no suggestion that the non-responders weren't exercising properly, it was simply that the exercise they were doing was not making them any aerobically fitter.

Jamie and his collaborators investigated the reasons for these variations and discovered that much of the difference could be traced to a small number of genes.

On the basis of this finding they have developed a genetic test to predict who is likely to be a responder, and who is not. Jamie offered me that test. But I would not be told the results until I had completed my HIT regime.

I agreed, had blood taken and went through some baseline tests to assess my starting point, fitness-wise. Then I began to do HIT.

Full throttle

It's actually very simple. You get on an exercise bike, warm up by doing gentle cycling for a couple of minutes, then go flat out for 20 seconds.

A couple of minutes to catch your breath, then another 20 seconds at full throttle. Another couple of minutes gentle cycling, then a final 20 seconds going hell for leather. And that's it.

Michael Mosley tries high intensity training

So how does it work? According to Jamie, and other researchers I spoke to, part of the explanation is (probably) that HIT uses far more of our muscle tissue than classic aerobic exercise.

When you do HIT, you are using not just the leg muscles, but also the upper body including arms and shoulders, so that 80% of the body's muscle cells are activated, compared to 20-40% for walking or moderate intensity jogging or cycling.

Active exercise also seems to be needed to break down the body's stores of glucose, deposited in your muscles as a substance called glycogen. Smash up these glycogen stores and you create room for more glucose to be sucked out of the blood and stored.

Somewhat sceptical I went off and dutifully did my four weeks of HIT, making a grand total of 12 minutes of intense exercise and 36 minutes of gentle pedalling. I then went back to the lab to be retested.


The results were mixed. My insulin sensitivity had improved by a remarkable 24%, which was extremely satisfying, but my aerobic fitness had not improved at all.

I was crestfallen, but Jamie was not surprised. It turns out that the genetic test they had done on me had suggested I was a non-responder and however much exercise I had done, and of whatever form, my aerobic fitness would not have improved. My dreams of winning Olympic gold ended there and then.

I will continue doing HIT because I can see the benefits. It won't suit everyone, because although it is short, it is extremely intense. Like any new exercise regime if you have a pre-existing medical condition you should consult your doctor before trying it.

Michael Mosley presents Horizon: The Truth About Exercise is on BBC Two at 21:00 GMT on Tuesday 28 February 2012 or watch online afterwards at the above link.


More on This Story

The BBC is not responsible for the content of external Internet sites


This entry is now closed for comments

Jump to comments pagination
  • rate this

    Comment number 243.

    Is it the first of April today?

  • rate this

    Comment number 242.

    Take a look at the Canadian Airforce Exercises 5BX plan from the early 1950's. Its the same principle in that you do a maximum of 11 minutes every day. You do get very fit, improve lung function and lose weight comparatively painlessly. Its also tailored to your age. I've used them for years (I'm 53) and parents of friends still use them!

  • rate this

    Comment number 241.

    This is nothing new, I've being having 3 minutes of intensive 'exercise' per week for years.

  • rate this

    Comment number 240.

    Chris Boardman, Olympic cycling gold medallist, pioneered a form HIT in his back bedroom at home. Most cycling "experts" said he wouldn't succeed as he wasn't doing "the miles".

    However he went to prove them all wrong. He was obviously a super responder.

    What we need now is a genetic test so that I can take it and know whether I need to be active 3 hours a week or 3 minutes!

  • rate this

    Comment number 239.

    We train almost everyday, doing workouts like 2x400, 2x300, 2x200, 2x100m (with a couple minutes rest in between each sprint) and that itself is more than three minutes of running. Now I'm not suggesting that everyone needs to train like track athletes, but there really is no easy way out. To expect visible and measurable results with HIT, there WILL be pain and sacrifice. But you WILL save time.

  • rate this

    Comment number 238.

    I've been a strong supporter of HIT since it became popular in fitness publications in the early 2000's. I urge readers of the article not to fall into the trap of "What I do works for me, HIT must be wrong". HIT pushes your aerobic capacity higher than 'slow' exercise, leverages the fact that most fat loss happens AFTER exercise, and helps to avoid using muscle protein to fuel sustained exercise.

  • rate this

    Comment number 237.

    There's some mileage in this...I used to weigh nearly 18 stone when I was 34, and started a programme called 5BX - 5 exercises to be completed in 11 minutes per day (2 Min Stretch, 1 min sit-up, 1 min chest/leg lift, 1 min push up, 6 mins run on spot - through 6 charts progression). I ended up losing 5 stone in 6 months.

  • rate this

    Comment number 236.

    #202 I swim at quiet periods: early in the morning or just before rush hour in the evening. The pools open but its very quiet (which is why I go then)

    #197 'Combat Fitness Assessment' has military relevance but its a damn stupid exercise. In the mid-90's the army was somewhat behind on good exercise practice. Running in step with extra weight on your back left a lot of recruits with injuries

  • rate this

    Comment number 235.

    It's another one of those programme item gimmicks only fit for Daytime TV. Whereas Horizon has improved its presentation of late, some of the broadcast content is still either rehashed or plain bonkers! This article is one example of the latter. I read through the article above and at the end noted a certain genetic disposition is a prerequisite for it to work. Surprise, Surprise!

  • rate this

    Comment number 234.

    Years ago a European coach called Franz Stampfl invented something called Interval Training. It consisted of a sequence of very short periods of very intense activity with recovery periods of about a minute between. It worked very well for competitive swimmers in the 1950s as I know from first hand experience. No one then suggested that you only needed to do it once a week; I did it twice a day.

  • rate this

    Comment number 233.

    I will preface this comment by saying that I'm a track & field sprinter and long jumper at a D1 University in the states.
    High intensity training is essentially what sprinters do non-stop for conditioning (that is, during pre season). It's super effective and has been shown to improve VO2 max and a whole host of fitness markers, but in my honest opinion, a total of 3 minutes a week is laughable

  • rate this

    Comment number 232.

    I do feel we underestimate what we are capable of. Once, it was accepted that you were over the hill at 30, ready for the old-folks home at 50. Nearly 50 myself, I'm regularly completing 7,500m+ in 30 minutes on a concept2 indoor rower, am around 52m for 10k and 1hr 50m for 1/2 marathon road running. I've still some way to go to beat my mum whose 1hr 15m 10k time isn't bad for a 72 year old.

  • rate this

    Comment number 231.

    224 Coupe...could tell the difference.

    Coupe, you need a sleeping pill.

  • rate this

    Comment number 230.

    My namesake Eugen Sandow (1867-1925) maintained that anyone could fit by following 19 exercises taking no more than 20 minutes a day. This was targeted at our late nineteenth century ancestors who felt just as stressed and time poor as we do. Three minutes a day is not enough! see for more details of a regime that actually worked....

  • rate this

    Comment number 229.

    Not exactly new though. Plan 5BX I understand was developed for the Royal Canadian Air force in the 1950's and was hugely popular when published to the general public in the 1960s.

  • rate this

    Comment number 228.

    That's why a splinter can't go and do a marathon"

    Especially if the splinter is in your foot.

  • rate this

    Comment number 227.

    26 HamAndStilton
    "Come on, this is utter nonsense. Anything[sic] who regularly runs or keep fit will tell you..."

    Of course - and it's absolutely clear that "what anyone will tell you" is much more true than any amount of scientific research.

  • rate this

    Comment number 226.

    As far as the aerobic fitness findings are concerned, I've read about the significant benefits to pro cyclists of short bursts of HIT (as opposed to the usual longer interval training). Pro cyclists, though, by definition, respond positively to training anyway - I'd imagine they would virtually all be 'responders' in genetic terms. (How do the rest of us find out which camp we're in?)

  • rate this

    Comment number 225.

    most people think of fitness as being not fat . To get fit for life, whatever you do ,do not over eat and in this normal state 3 to 5 minutes intence exercise works. 78 years and still going strong.Just had a stroke and afterwards open neck surgery and no after effects due to strongfit body.

  • rate this

    Comment number 224.

    I started doing this about a year ago, I'd walk on the treadmill for 1 minute while stretching, then turn it up very fast for 1 minute and repeat it up to 4 times, it was an ideal warm up for weights. Within a month I was finding myself MUCH fitter. I was already cycling 30 miles+, playing 1 hour football, 1 hour badminton and 3 weight sessions per week and I could tell the difference.


Page 5 of 17


More Health stories



Copyright © 2015 BBC. The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.