There were times during the sunny lockdown last spring when you might have mistaken my local park for some sort of idealised Victorian sanatorium, filled with joggers, skippers, stretchers and barbell-raisers. On the deserted roads nearby, families cycled in liberated gaggles. Inside living rooms, children started the day by doing star-jumps with their parents. It felt like a new start.

There was only one problem: it was a mirage. Subsequent research by Sport England found that overall activity levels fell dramatically for both adults and children. During the pandemic, an ongoing crisis became even worse.

And crisis it is. Even in normal times, about four in 10 British adults are so immobile they risk their long-term health. Around 25% are almost completely inactive, meaning they exert themselves for less than 30 minutes a week. For children, almost eight in 10 fail to amass the hour a day of movement seen as vital to prime young cardiovascular systems and lay down bone density.

In non-Covid times, ill health from long-term inactivity is blamed for about one in six UK deaths, about 100,000 a year, and around 5 million globally. If a twentysomething lives between an office chair and a sofa, it could be several decades before associated ailments such as heart disease, type 2 diabetes or cancer show themselves.

The fact that regular physical exertion is good for your health was confirmed in 1953, through the work of epidemiologist Dr Jerry Morris. His breakthrough came when he tried to work out why London’s bus conductors had about half the rate of heart disease of the drivers, eventually connecting this to the 500-plus staircase steps they climbed each shift.

More… ‘Inactivity is an ongoing pandemic’: the life-saving impact of moving your body | Fitness | The Guardian