Fast Exercise is Dr Michael Mosley's follow-up to his 5:2 diet bestseller. Together, he and co-author Peta Bee are a dream team

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In the introduction to Dr Michael Mosley and Peta Bee’s newly released Fast Exercise book, Michael muses that:

“Diet and exercise are complementary, they go together like Fred Astaire and Ginger Rogers, like Batman and Robin.”

By this token, it was only a matter of time before the medical journalist followed up on the immense success of The Fast Diet  with a similarly straight talking companion to physical exercise. Those of us who enjoyed his BBC Horizon series were waiting with bated breath for the publication of Fast Exercise - a book revealing the benefits of High Intensity Training  (HIT, or High Intensity Interval Training as it’s also known).

Playing Robin to Michael’s Batman is fitness writer and GTG columnist Peta Bee . It’s a dream team: one a self-declared ‘slob’, one an exercise ‘dynamo’. Between them they play on their strengths and encourage readers to do the same. Michael demystifies the science behind HIT, and Peta shows you how to do it, whether you relish working out as she does or are more of a sweat shirker like Michael. Both plainly present the far-reaching benefits and minimal drawbacks of HIT as we currently know them. There’s no fluff, no harebrained theories, no aspirational “Fitspo” photoshoots, just facts, quips and practical tips. Just like HIT itself, there’s no messing about.

The book begins by exposing the ‘Truth About Exercise’ as we presently understand it - as previously thought, it’s good for you, but it seems that those lengthy Mr Motivator style aerobic workouts of the eighties have something to answer for. As Mosley highlights, ‘There is a huge gap between what sports scientists know about exercise and what is actually done in gyms and public parks’.

Recent studies prove that it’s not the duration on the workout that matters; it’s how hard you work. When you challenge your muscles and cardiovascular system during exercise over time, the benefits are myriad, from burning fat to boosting brain power. The ‘time’ factor here is key; Michael reviews the scientific literature, and moderate-intensity activity done for long periods emerges as lacking when compared to briefer bursts of activity performed at a higher intensity. From fat burning to increasing aerobic fitness to lowering blood glucose levels and curbing appetite, short, sharp and up to speed is the way to go according to Mosley, Bee and a host of academics, scientists, fitness experts and medical authorities.

Countless studies back this up, and as Mosley underlines, HIIT training is not a new phenomenon; it’s the training method adopted by Roger Bannister previous to breaking a world record by running a sub-four minute mile; Sebastian Coe used it and subsequently won Olympic medals and hunter-gatherers were onto something when it came to both intermittent fasting and HIT. As Peta emphasises, even kids have it more sussed than we do when it comes to frequent blasts of activity, little and often. We’re talking less-is-more time wise, with greater health benefits and a higher chance of shedding the pounds than mindlessly slogging away on the treadmill. Stop the clock; we need to know how to get on board with this HIT business, which is where ‘The Workouts’ section comes in.

Peta’s workout guides offer a diverse range of exercises to suit most adults, no equipment or sporting prowess required. Mosley doesn’t even bother with a gym kit, and given that the first stage of his preferred workout is ‘Put the kettle on’, you’ll observe that he’s as ‘real’ as the average gym-dodging Brit comes. Unflattering images of squats in the middle on the book confirm this. Nevertheless, despite the fact that Mosley doesn’t ‘respond’ to exercise as Peta does (the book features an interesting discussion on the subject of ‘responders’ and ‘non-responders’), since adopting HIT he has kept his weight in check and improved his glucose tolerance, not to mention lowered his risk of dementia and improved his mood. Adonis frame or not, these should be reasons enough to jump in the saddle, especially if the ride is a short one.

If you’re after a comprehensive, detailed workout manual, Fast Exercise might not meet your expectations. The workout options are varied and easy to fit into your daily routine, but I think I’d need some assistance from a personal trainer type to master the Fast Strength techniques. I also feel that I’d need someone on hand at first to really push me into the high intensity bracket; if you don’t reach your peak, you’re just going through the motions for a reduced amount of time.

Likewise I’m a bit in the dark as to how the morbidly obese and extremely unfit would make HIT work for them. That said, Peta’s lifestyle advice is down to earth and makes incorporating and prioritising HIT seem both simple and achievable. Her nuggets of wisdom aren’t prescriptive, just really helpful, and both herself and Mosley give you all of the evidence and information you need on the subject. It’s up to you what you do with it.

The overarching message is that fitness shouldn’t be faddy, overly punishing or eat up your day. It should be as automatic and time-efficient as brushing your teeth. Despite the apparently miraculous efficiency of HIT, Mosley is keen to emphasise that a few dynamic exercise sessions per week are not a cure-all. We are chained to our chairs and we all need to move more. HIT may be something of a fitness revolution, but Mosley indicates that our physical environment also encourages us to be sedentary. If our environment changed and challenged us to burn more calories, we’d be healthier, fitter and slimmer without making much perceivable effort. Now there’s an idea.

Fast Exercise: the simple secret of high intensity training: get fitter, stronger and better toned in just a few minutes a day, £7.99, 

To find out  how HIIT works and for a HIIT workout plan, see our video with Steve Mellor  of Freedom2Train. Read more about  the Fast Diet here .