The new school year has seen us quickly hit our stride: football practice (x 2); football match (x 2); gymnastics (x 2); cricket practice; refereeing course; dance class; piano lesson. Three children and ten different weekly out-of-school activities to organise in a plan that must allow for domestic duties, as well as Mother in the Middle and my slim extracurricular interests. Among the pursuits that get too easily crowded out is anything that allows us to exercise and keep fit. Until some way of harnessing our kids’ running, bounding and cartwheeling into our own metabolism is found, we need to get out and exercise ourselves, lest we slip with elevated blood pressure, atrophying muscles and impoverished lungs over the cliff edge at the far end of our forties.

For a year or two I had this dilemma of mixing the kids’ activities with my own exercise cracked. During no.2 son’s football practice, my touchline pal and I would go running. We had the option of running along the canal, around the water park or, if the gate was left open, around the running track. There, I discovered that Mo Farah would complete a 10,000 metres in less than the time it took me to run half that distance. I would however, nudge ahead of Usain Bolt in a sprint that involved him running twice as far as me.

But last season, our sons started playing competitive fixtures on Saturday mornings. My pal and I ditched the running in favour of something far more thrilling: spectating our boys’ matches.

There is, of course, the option of playing with the kids. We kick around in the garden and sometimes in the park. I play with them just enough to know that they play more physically, at greater pace and belt the ball harder than me – and the risk of injury playing with children is well understood.

So I have looked for new opportunities to get my exercise.

A new leisure development close to work has given me the chance to swim in my lunch break or at the start of the day. Determined not to flap up and down the pool doing breaststroke, I took a short course of lessons and have worked hard on the crawl. Stringing together, first eight, then twelve and finally 20 lengths of crawl – before breaking for a few minutes of genteel breaststroke – gives me great satisfaction. Thirty minutes of swimming leaves me fulfilled and fatigued from my shoulders, all the way down my body and legs. When I’m in the pool, I’m definitely not just going through the motions.

Last week, held up in a meeting, I narrowly missed my lunchtime window for swimming. Edgy all afternoon, I agreed a late return home, so that I could swim after work instead. I arrived at the pool as the lessons were ending. Heading from the showers, I stood to one side while the school kids piled into the changing room. I was first into the pool and swam a couple of lengths before a lifeguard bent down to me and asked me to come out while his team prepared and checked the pool. Two of his colleagues wound in the lane ropes, while he patrolled the pool carrying a net on a long pole. I shivered on the side, waiting for the nod to restart.

The man with the net said it all looked clear, but then got into a discussion with a lifeguard. They pointed at the middle of the pool, then looked at me. “Could you, with your goggles, check out the middle of lane three?” net-man asked me. I stepped back in and waded across to the lane, as net-man continued, “we think one of the kids had an accident.” A sticking plaster, I began to think.. “But it’s fine as long as it’s not diarrhoea. The chemicals make it safe.” Right, a poo. “Could you check?”

I ducked under, swam a little way and there at the bottom of the pool was the accident. I surfaced, confirmed the sighting and began wading towards the side. “It’s fine, because of the chlorine”, the net-man repeated. “We don’t have to close the pool.”

The lifeguard and net-man looked at each other, then at me. They were in t-shirt, shorts and trainers and were dry. I wasn’t. Holding out the net to me, he asked, “Would you mind catching it for me?”

With all the aplomb of the sanitation engineer that I’m not, I took the net and after a couple of swipes made the catch and returned the net, receiving thanks and further reassurances of the efficacy of the chemicals. I then swam 40 lengths, eyeing the pool floor suspiciously. I showered and at home took a bath.

A few days later I told some colleagues the story of my odd job at the pool. “You didn’t really go swimming,” someone said. “Oh, yes I did.” “No,” he countered. “You were just going through the motions.”