In the latest round of scolding women and pretending it’s for their own good comes the news that we’re not doing enough exercise – at least of the “vigorous” sort. According to Nuffield Health, 47% of women they surveyed hadn’t engaged in activities such as running, swimming or a class at the gym that would help them to keep fit and healthy in mind and body; markedly more than men, of whom only just over a third responded similarly. Two-thirds of the women, and half of the men, cited a lack of motivation; other reasons included not knowing where to start, and simply not having enough time.

To be clear, it’s not Nuffield doing the telling-off – more what we might call the discourse that greeted their findings, which immediately started to discuss issues of childcare deficits and the heavier burden of unpaid labour that continues to fall on women and prevent them from getting to Zumba. But although these barriers to exercise are demonstrably valid, they also reinforce the idea that we are failing to do something we ought.

Despite an early and traumatic encounter with a school vaulting horse, I come to praise crunches, not to bury them. Looking after your physical self is clearly worthwhile, especially when the march of time threatens creaking joints and energy dips; and we all feel better after a bracing walk (it is widely reported).

It is perhaps the notion of vigorousness that prompts my caution, not least because it is surely subjective and doesn’t take into account an individual’s starting point. For those who are unfit, or with mobility and other health issues, one person’s cool-down might represent an unattainable goal (apparent or actual). Nuffield does recommend an incremental approach – work up to your daily 10,000 steps by starting with 2,000, for example – but even that rough mile will be daunting to many.

Others have a more Bartleby-like response to exercise: they would simply prefer not to, perhaps out of a visceral dislike, or they find it boring, or because their time is filled with things they regard as more important. Perhaps, indeed, those things are more important: they involve caring for others, or volunteering to help those outside one’s own circle, or even getting to grips with larger personal problems than slack muscle tone. I phrase it like that – rather than maintaining cardiovascular health or building core strength – because the dividing lines are still blurry between physical fitness and the presentation of one’s outer body to others, no matter how many recipes for chia seed smoothies the wellness industry pumps out.

It is hard, of course, to imagine a modern-day equivalent of the American fitness instructor Debbie Drake, who in 1960 became the first woman to present a daily fitness TV show and who released an album entitled How to Keep Your Husband Happy. (If you are in need of a fillip between squats, do glance at her appearance on the Johnny Carson show, in which she, in frilled yellow leotard and sheer black tights, inducted the talkshow host, who had least removed his suit jacket but not his tie, into the magic of hip undulations.) But the message that, nowadays, keeping fit is primarily a duty of care to oneself, is so often betrayed all around us, sometimes subtly and sometimes egregiously.

Thus it is, for instance, that the body positivity movement has to contend with the outpouring of concern over the health of larger women, when the merest excavation reveals that concern to be disgust and repulsion.

Rather than despairing at our own failure to measure up, redefining success might help. On a podcast about books that I present, my co-host and I regularly begin with a two-minute chit-chat about gardening, and the horticultural element of our postbag greatly outweighs the literary. While deadheading might not be vigorous, digging over a veg patch certainly is, and so is mowing, and large-scale pruning and humping about sacks of well-rotted manure. Why should that not count as my exercise, and elevate me out of the benighted 47%? Ditto kitchen disco, pet-wrangling, the countless trips up and down the supermarket middle aisle and wrestling a super-kingsize duvet into its cover?

Meanwhile, the world outside our bodies needs our attention: as almost everyone has noticed, we’re not doing so well. A healthy body and mind might indeed help us to navigate the challenges to come, but self-flagellation surely won’t.

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