Although kids today, I argue very often, have everything much easier than in the 1980s – Asos deliveries, iPads, 4G, better, less flammable hair products and so on – I have great sympathy for one new development on Planet Teenager: the war on “sick-note culture”.

In a bid to fight obesity and other future health woes, schools across Britain such as the Blue School in Wells, Somerset, are now insisting their pupils take part in PE lessons even if they have a sick note penned by their parents. No more Get Out of Games Free cards for teens like me who would have rather died in a house fire than publicly Fosbury Flop. It’s either produce an official certificate from one’s already oversubscribed GP surgery – good luck with that – or you’re out there in an Airtex vest doing star-jumps with the rest of the poor sods.

This is a sad time indeed for slackers, shirkers and those far too cool to run. I was a goth when I was 13, a sub-species not given to athletic endeavour. The darkness enveloping their souls prevents most sudden movement. Crimped fringes makes them a potential death trap with a javelin. But the goth’s plight is nothing compared to the modern Instagram-obsessed teen labouring under harsh pressure to radiate cool vivaciousness at all times.

Because no one is truly cool wheezing around the 800m track 17 minutes after the winner – some long-limbed thing with a bum like two happy clementines – left for the showers. Very few of us are “OMG totally gorg, like a princess, hun!” in regulation gym-knickers heaving a shot-putt about. Today’s teens find that any of life’s calamities can be potentially filmed and uploaded on Youtube with merciless relish. It’s little wonder so many young people loathe PE. At a time of life when one’s body is growing, wobbling, spurting hairs and emitting a cacophony of spots, pustules and smells here are two hours a week when you are obliged to take your pants off and reveal the majesty of its awfulness.

Furthermore, I may have been naturally academic, but I was depressingly mediocre at anything sporty. It was no fun, I decided, doing things you’re not terribly good at. Let me, instead, pick apart Chaucer in the library. Let me read Jackie Collins smut behind a pile of crashmats.

“Dear Sir/Madam,” one of my typical sick notes, back then, might have said. “Sadly, Grace will be unable to do cross-country course today due to a hideous pain in her abdomen which may or may not be oncoming appendicitis.” None of your migraines or tickly coughs. The trick was to find a malady with such grave potential that even changing into Dunlop green flash plimsolls might exacerbate it.

But now, quite rightfully, the schools are fighting back. It hasn’t helped that “How to write a sick note” websites had sprung up to help pupils with useful swinging-the-lead parlance. I fear for our country’s security if this is the calibre of kid hoping to work for MI5. More seriously, a survey by Chance to Shine – a charity that promotes cricket in schools – found that parents who spent their own school days trying to skip PE were five times more likely to help their children bunk off.

Sick-note culture, it seems, is passed down through the generations. Shirkers beget shirkers. Fat bums beget even fatter bums. I do not have children and am against mollycoddling, but if I did, I know I’d be hard pressed to resist a saucer-eyed plea to avoid PE. How do you say no to a child pleading to avoid the shame of coming last in their year at hurdles and their shame spread virally across Facebook? Clearly some children today are too tightly nannied, but many others have sensitive – perhaps overly empathetic parents – still scarred decades later by the horrors of being “bad at games” and the horror of the communal shower.

Of course, the great irony, and one that PE teachers are hamstrung to address, is that in later life many adults, as I did, have a sudden volte-face towards “keep fit”. Suddenly exercise reveals itself not only as a good idea, but terrifically good fun. Mood lightening, life affirming, tension releasing. Many, many of the individuals who retreated, in their later youth, into loud nightclubs and all-night warehouse parties to null the pain of teenage awkwardness and hideous memories of PE lessons, then suddenly find themselves aged 30-plus stepping out of a SpinCycle class in damp Lycra feeling as high as a ruddy kite. Exercise, it turns out, feels better than boozing, snogging and snorting lines of dubious substances. Better than a dozen Instagram likes or a list of fatuous comments from internet frenemies scouting for attention.

“Why did no one tell me before that exercise feels this good?” they think, somehow overlooking that they were indeed told. Of course they were told. Their parents told them, their games teacher told them, their GP told them, the local council told them and the government told them, to no avail, on around 678 occasions over the previous 20 years. The magical formula of pushing less into your face and moving about more often will lead, beyond doubt, to a slimmer, more radiant you.