The Miracle Pill author Peter Walker: It's never too late to start exercising

Now Walker has embarked on another groundbreaking investigation into what he says is a health crisis more deadly than obesity.

The UK-based journalist says sedentary living, recently exacerbated by COVID-19 lockdowns, is causing a pandemic of chronic ill health which experts predict could soon bankrupt public health systems.

In his new book The Miracle Pill: Why a sedentary world is getting it all wrong, Walker examines this unexplored health crisis, and looks at the people and initiatives trying to turn it around.

He asks why, when we're bombarded with images of fitness and sport, are one in two adults and 80 per cent of children not getting enough exercise.

"What for centuries was universal and everyday has become the fetishised pursuit of a minority, whether the superhuman feats of elite athletes, or a chore slotted into busy schedules," he says.

Could the answer be, he asks, what scientist call 'the miracle pill'.

"What is the miracle pill, the simple lifestyle change with such enormous health benefits, that, if it was turned into a drug would be the most valuable medicine ever created?" he asks.

The answer: activity, or movement.

"And the good news is that it's free, easy and available to everyone."

Despite this, 1.5 billion people around the world are so inactive they are at greater risk of everything from heart disease to diabetes, cancer, arthritis and depression, even dementia.

So how can you encorporate more movement into your day, and is it too late to make a difference?

No, as Walker writes in this extract from his new book, it's never too late to start being active.

For all that some people do embrace gym-going or other forms of activity and exercise in later life, there are plenty who quietly conclude that after decades of immobility, there might not be much point.

This could not be more wrong.

There is, seemingly, never an age point at which regular exertion does not bring benefits.

Countless studies have shown that, even among notably old- age test subjects, programmes of aerobic or resistance activities, or both, coupled with balance and flexibility work, can not just slow the gradual decline caused by the advancing years but reverse it, making continued independent living all the more likely.

The good news is that you don't have to be running marathons to feel the health benefits of latter-age activity.

It's worth remembering that in terms of exertion, moderate and vigorous are relative terms, and as you age the amount needed to push your body into the magic zone beyond three METs necessarily becomes less.

There is emerging evidence that in older age relatively tiny amounts of movement can do a lot of good.

And this is not just about physical welfare. It is also true for what many activity experts consider perhaps the most exciting and fast-moving area of activity research: the mounting evidence that regular movement can ward off Alzheimer's and other forms of dementia, as well as giving an overall boost to cognitive function.

Some studies have even shown that it can reverse the shrinking of the brain that otherwise happens as we age.

Kirk Erickson, a professor of psychology at the University of Pittsburgh and one of the world's foremost experts in how activity can help the ageing brain, tells me: "We think that starting earlier in life is probably better, as is the way for most things. But that doesn't mean it's ever too late to start

"And that's an important message. Some people that come into my studies say, 'Well, I've never exercised in my life, it's probably too late for me.' And I like to tell them that it's never too late.

"It's a shame that sometimes people start thinking that they're on an inevitable trajectory, and there's nothing they can do."

One thing that is abundantly clear from dozens of studies is that the more active and fit someone is in older age, the better their chances of living even longer.

We have already seen that activity has been shown to seemingly slow the ageing process by limiting the shortening of telomeres, the end-caps for our chromosomes.

The study we saw before estimated the benefit at around nine years. Others have gone higher - one UK research paper said the most inactive of a group who had their telomere length measured 'may be biologically older by ten years compared with more active subjects'.

One US study that examined the fitness of more than 4000 sixty-pluses found, a dozen years later, that those in the upper 40 per cent of tested fitness were around half as likely to have died as those in the bottom 20 per cent.

An even longer-term study, over 21 years, found that 15 per cent of older members from a California running club died over that period, against 34 per cent of same- age non-runners.

Even more strikingly, when age-related disability was measured, while it took the non-runners just 2.6 years on average to start finding some everyday tasks difficult, for the runners it was 8.7 years.

It's worth remembering that this is about lifelong fitness, not just a previous history of activity - exertion must be maintained and regular for its benefits to be felt.

A decline in independent living can take many forms, and can be mental as well as physical.

One UK study which tried to project the future scope of so- called multi-morbidity - the prevalence of a series of chronic conditions in one person - found that in 2015, more than half of Britons aged 65 and over had two or more conditions from a list including arthritis and high blood pressure - the two most common - as well as diabetes, cancer and dementia.

By 2025 this proportion was expected to increase to almost two thirds.

Another crucial factor is bone strength, particularly for women, whose bone density diminishes after the menopause.

Osteoporosis, the chronic condition caused by low bone density, is one of the major causes of impairment, and often death, in older people, causing an estimated 9 million fractures a year worldwide.

Osteoporosis groups say the condition affects 10 per cent of women in their sixties, 20 per cent of those in their seventies, and 40 per cent of those in their eighties.

But while, as we saw earlier, a considerable proportion of bone density is laid down in youth, it is once again never too late to start.

Numerous studies have shown that activity can halt or even reverse the age-related decay of bones, and make fractures less likely.

Part of the picture is also preventing falls in the first place, which is a function also of strength and balance, hence the importance of muscular training.

Professor David Buchner from the University of Illinois is one of the world's best-known experts on inactivity science. He spent nine years in charge of physical activity for the US Centers for DiseaseControl and Prevention, and chaired the group that wrote the American government's first official guidelines on the subject.

Much of his recent work has been connected to how strength- based activity and balance exercises can prevent falls in older people.

"It is amazing," he says. "I mean, an older adult can reduce the risk of a fracture by 40 per cent by doing these balance exercises and lumbar strength training.

"We're not talking training Olympic athletes here, we're talking about fairly modest, moderate amounts of physical activity on a regular basis. And it has that level of effect on older adults."