5th July 2022

Michael Mosley’s 21 Day Body Challenge

Dr Michael Mosley’s three part show, Michael Mosley’s 21 Day Body Challenge, airs in Australis on Wednesday 6th July on SBS. For those in the UK, you can watch the show “21 Body Turnaround with Michael Mosley” on Channel 4 catch up. 

Are you out of shape, mentally and physically, after 14 months of lockdown? 

Join the club. There’s been a lot of focus on weight gain during the months we’ve all spent at home – one recent survey suggested we’ve put on an average of 10lbs since the pandemic struck.

But our fitness levels have also suffered – although some have discovered the joys of moving, whether it’s online workouts or simply walking, others have allowed their fitness to slip.

Indeed a recent survey by Sport England found that the first lockdown led to an ‘unprecedented’ fall in activity levels, with 3 million more adults becoming “inactive” ie doing less than 30 minutes of exercise a week

And while exercise along is unlikely to lead to weight loss (I’m afraid that’s what the studies show), it’s absolutely vital in so many other ways: being active and fit means better health, better mood and even a better sex life.

And don’t be daunted by what you might think is involved in getting fit: the really brilliant thing is that you can safely overhaul your fitness labels in a remarkably short time, even if you currently consider yourself a ‘couch potato’.

That’s one of the key findings of my series, Michael Mosley’s 21 Day Body Challenge, which airs on SBS in Australia on Wednesday 6th July. (Available to those in the UK on Channel 4 on Demand – 21 Day Body Turnaround with Michael Mosley).

21 Day Body Challenge

For the series, we took five brave volunteers, ranging in age from 29 to 59, who were overweight or obese, very unfit and keen to do something about it. I asked them to follow a healthy, low calorie, intermittent fasting diet and combined this with an exercise regimen based on HIIT, High Intensity Interval Training.

The health turn-around they achieved in just three weeks was remarkable.

Although they struggled to do something as simple as walk up a hill, when we first met, most of them had been active, before lockdown.

For instance, 42 year old Wayne, used to be a keen cyclist, regularly cycling from home to work, before he swapped time on the bike for booze and takeaways. The same was true of 32 year old Katrina, who used to love a good workout, before the birth of her son and the closing of her local gym made that so much harder.

Before starting we put our five volunteers through extensive medical tests, which revealed that despite being relatively young- they are mostly under 40- their bodies and brains were already showing signs of premature ageing. They had high blood pressure, high levels of depression and anxiety and too much fat around the waist.

But what I found especially shocking were their VO₂ max scores…

A precise, scientific measure of aerobic fitness and how strong your heart and lungs are. VO₂ max is the maximum amount (V) of oxygen (O₂) per minute your body can use while you are exercising.

It is an extraordinarily important number because it is one of the best predictors we have, not just of fitness but whether you will lead a long, happy and healthy life. A high VO₂ Max has been linked to a reduced risk of heart disease, cancer and dementia, as well as lower levels of depression and THAT higher sex drive I mentioned earlier.

A recent study of 80 middle aged men researchers found those with a high VO₂ Max score were 10x less likely to suffer from erectile problems than those who were sedentary, while in women VO₂ max was a powerful predictor of sexual arousal.

The good news is that, whatever your age, you can improve your aerobic fitness in a surprisingly short amount of time.

How to measure

The best way to measure VO₂ max is to go into a lab and run on a treadmill while wearing a tight-fitting mask that measures how much oxygen your body is taking in. The instructor pushes you to exercise as hard as you safely can.

If you are a super fit athlete then your body will be able to take in, and use for energy, at least three times more oxygen per minute than someone who is much less fit.

If you don’t have access to a lab, then you can estimate your VO₂ max by doing the simple Rockport One Mile Fitness test – you walk a mile, as briskly as you can, then measure your heart rate, and how long the walk took you, when you stop.

An even simpler, but cruder way to estimate your VO₂ max, is to enter your resting heart rate – which you can measure at your wrist – into an online calculator (you can easily find these online). Once you have your score you can compare yourself on a chart, with the sort of score expected for someone your age and gender.

My VO₂ Max is 38, which is good for my age (I am 64) and more typical of someone in their 50s.

When we tested our five volunteers we found their VO₂ Max scores were, in most cases, typical of someone at least ten years older and, in one case, more than 30 years older.

So, along with their new diet, we asked them to walk more – trying to get in 10,000 steps a day. We also asked GP and personal trainer, Dr Folusha Oluwajana, to put them through an exercise regime which included 20 minutes, twice a week, of High Intensity Interval Training – HIIT.

High Intensity Interval Training – HIIT

HIIT involves short, but intense bursts of exercise, interspersed by short recovery periods. You might, for example, do 30 seconds of star jumps, followed by a short breather, then 30 seconds of squats. And so on, for up to 20 minutes.

How does it work? Well the first 30 second burst of exercise leads to the release of so-called “signalling molecules”. When you do your next 30 second burst, these signalling molecules are activated and help stimulate the growth of things like your heart muscle. Doing this regularly leads to big improvements in aerobic fitness in a remarkably short amount of time. But it is intense, so if you are currently very unfit or on medication do talk to your doctor first.

Our HIIT regime, when combined with time restricted eating (eating only within a 10 hour window each), a far healthier diet (recipes were provided by my wife, Dr Clare Bailey, Instagram.com/drclarebailey), and a bit of cold water swimming, had an amazing impact on my 5 volunteers bodies and brains

I won’t spoil the series by giving away too much, but they managed to lose a lot of weight, get better sleep, reduce anxiety and massively improve their aerobic fitness, knocking years, and in one case, decades off their earlier scores. And all in 21 days.

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