I remember the first time I ever did a bear crawl; this was my opening encounter with primal fitness, like the life of the ancients – nasty, brutish and short. It is as it sounds: you crawl with only your hands and feet touching the ground, to the top of the mat, or whatever space you’re in, and back. It’s extremely hard work and every second feels like five minutes. It also felt to me quite imprecise – it’s hard to check your posture when you’re scrambling about, difficult to say what muscle group is taking the strain until you check what hurts when you wake up the next morning.

And that’s more or less the primal blueprint, though it can take many forms; it’s designed to replicate the physical behaviours of our ancestors, who – according to fitness lore – were much fitter than we are, could run farther, pick up larger items and beat each other to death more economically. Sorry, that was a red herring, there is no boxing element.

At the gym it involves quite a bit of equipment, and don’t ask vexing questions about whether they would have had tractor tyres in the stone age. At home, without atlas stones and sandbags, it’s more about animal flow, using your body in ways modern life never seems to allow for: spending time on all fours, squatting, loading the bits of your body that your civilised life has atrophied. The trainer Charlène Gisèle divides her primal workshop up by animal: the bear crawl and the donkey kick you’ll recognise, the meerkat and the flamingo you probably won’t.

So here’s why it works: we all have an innate understanding of how individual animals move. If I said to you, “Do a full squat, then raise yourself to a half squat, then hold it, then back to a full squat”, you’d get into a tizz about what “half” and “full” connote in terms of depth, what to do with your hands, how straight your back should be. Whereas if I said, “Start in a squat, then rise like a meerkat looking for prey or its mates or whatever”, you would know what that meant. A cobra is a yoga move – lie on your stomach, then arch your chest up like a, well, like a snake (not to be confused with the sphinx, which is the same thing, only with your forearms flat on the ground in front of you). You don’t need a yoga background to try that out. You know what a cobra looks like.

A bunny hop, a starfish, even things you couldn’t picture impersonating with your own body (a peacock?), these all provide intuitive templates for the look you’re aiming for. With Gisèle, I did two minutes each of 10 animals, with a 30-second break between them – being movement rather than muscle based, each exercise is a bit more engrossing than traditional exercises, so you don’t realise till the end of each block how tired you are. The point is not sweating for the sake of sweating; it’s to reawaken muscles rendered dormant by a sedentary lifestyle and too rigid a workout regime.

What I learned

The bird of paradise move mimics their mating ritual: stand in the middle of a mat and tap the end with one outstretched leg and pointed toe. Then switch.

Playing up: three park games for the bank holiday

Best for fitness: plank races
Sort yourselves into two teams of even numbers. Choose a start and finish line about 20 metres apart, more if the team is large (six plus). Make sure everyone knows what they’re doing before they assume a plank position; five seconds spent in an unnecessary plank is enough to cause bad blood between friends. Get everyone lined up vertically, the person at the front with their head level to the start line. Once everyone is planking, the person at the back stands up, runs to the front, reassumes their plank and this continues until someone’s head is level with the finish line. Cardio and pain, what more could you ask of a park?

Most fun: donkey tag
Everyone tuck something into the back of your trousers; this is your donkey tail. Choose one person to chase and the rest to be donkeys. When the chaser successfully grabs your tail, you also become a chaser. Continue with this nonsense until there’s only one, seriously victimised donkey being chased by everyone.

Best for coordination: Frisbee golf
Frisbee on its own works for elemental release, but for a little more challenge and variety, make some goals with jumpers and aim the Frisbee at those. You can introduce forfeits (push-ups, jumping jacks) for people with terrible aim, if they’ll agree to that.