You can do one of three things with Good Gym: a mission run, where you run with others to an older person’s house and do a one-off task, like moving a bed so that a hospital bed can be moved in; a coach run, where you regularly run to visit someone who’s isolated; or a group run, where you all run to a community garden or similar project, do some gardening (or clearing, or building), have a fitness session afterwards, then run back.

This last option is what I did, and it was fantastically well-planned: a locked room to leave your stuff in; a community organiser waiting with trowels, gloves and tiger lily bulbs; a well-thought-out running route – we broke halfway there to do wall sits under a railway bridge. It was raining like mad. It has the precision of a military exercise, where you ask the very world of your squad but on the understanding that you’ve thought about where to dry their socks.

All runners’ clubs claim to be mixed ability, but this genuinely was. One guy had done a 35km hill run the day before. Two sisters from the Jesus Christ Church of the Latter Day Saints were dressed like Zammo from Grange Hill dodging a PE lesson. Yes, I was smirking on the inside about nuns’ athleisure. I belonged in Bad Gym.

We did a quick warmup in the street, during which we had to say our names and describe ourselves, which I did mendaciously (I like to chat, but I do not like to talk while running: I prefer to breathe). It was two kilometres down to the Kambala Cares community project.

Ana Hancock, who runs the Wandsworth branch of Good Gym, sets quite a lively pace, but other-Anna at the back, with infinite patience, made this a shame-free experience. There was no way you could be slower than her; she wouldn’t allow it. With a bit of messing about (wall sits, traffic lights), we got to the gardens in about 15 minutes.

Donna, head of the community garden, was waiting with three friends and a shopping trolley full of shovels. And all these fevered enthusiasts arrived like a herd of wet antelope – there were 20 of us (sometimes there are 40). It felt very English and wholesome and a bit like a Carry On film, even before the fitness session where we all started chasing each other.

The gardening took about half an hour, during which time 20 of us got a phenomenal amount done. “The funny thing is, I never do anything in my own garden, I wouldn’t know where to start,” one guy said. Same. But we must have planted 100 bulbs, cleared a terrace, weeded five beds. We learned running techniques in the park, then ran back, did a stretch.

There’s a reason human societies organised themselves into groups: everything is faster and more pleasing. This is much more than a carbon-neutral wheeze to sidestep the soul-sapping disconnectedness of driving to a gym to run on a running machine. It is environmentally positive, from the smallest to the greatest degree.

What I learned

Good Gym is nationwide – 50 areas of the UK are covered so far. Membership is a voluntary £9.95 a month, goodgym.org