It’s over 40 years since I rode a push-bike to Saturday afternoon sport, but humans, on the whole, have been riding bicycle-like contraptions for hundreds of years. Staying upright, then steering, is not as easy as it would first appear. And maintaining that seemingly effortless forward propulsion, is a complicated mathematical equation to do with body mass and physics, which I can’t possibly explain.

And I can’t possibly explain why, for reasons unknown to myself, for Christmas 2016 I bought myself a push-bike. As one of 12 children growing up in the country, I had never owned a bike that was solely, truly mine. Dad had managed to salvage a rusty old boy’s bike from the local tip, back in the day when you could come home with more than you took. I found it hard to love the second-hand, shared contraption with no gears and a solid seat that threatened to damage my future child-bearing capacities.

Before I bought the bike in 2016, I resisted and reasoned. I was in my sixth decade and therefore too old to start something new and potentially dangerous. My dodgy back and recurring pelvis injury made me wonder: would my body cope with this new activity? Would I outlay hundreds of dollars, only to have the thing sit in the garage, goading me every time I walked past, until eventually rusting to death? Would I be safe on the roads? And would it be any fun on my own, or just a figment of some childhood imaginings? Zig-zagging the white lines of rough bitumen with my younger sister often ended up with one of us nursing bloodied knees and elbows.

But then I read an interview with Cadel Evans – Australia’s only Tour de France winner – about his annual charity bike ride. He said his mother usually still rides in the 65km race along the Great Ocean Road in Victoria, and there was no turning back. I headed to the bike shop, with my husband tagging along to be the voice of reason.

They had three-wheelers with rainbow-coloured tassels hanging from handle-bars. Serious-looking bush-bikes, with thick, chunky tyres, stood on elevated stands, as though top of the pecking order and demanding a better rider than the rest. Solid, bold BMXs sat squat and challenging, daring me to choose them.

Just like Goldilocks, it felt right the first time I sat on it, a blue cruiser-style. I sat on lots of others, but kept going back to the blue one.

It didn’t fit in the back of the car, so I rode it home. With a little fear and a fair amount of trepidation I quickly got on to a back street and was home in about 15 minutes, my heart pounding. I propped it on its stand in the carport, feeling childishly giddy and out of breath.

I rode again the next day to meet a friend for coffee, a 15-minute ride each way. A few days later I rode for 40 minutes around a nearby lake, along a shared pathway.

I am awake early today. At 5am the air is still and has the freshness of dew in it before the humidity of the day steals it away. By 6.30am I’m cruising down the gentle slope beside our house on my blue bike. It’s only a 10-minute ride to a nearby bakery so I pick up a loaf of fresh bread for breakfast, toss it in the front basket and head home with surprising clarity of mind and a pleasant zinging in my legs.

The Harvard Health website says cycling is good for our heart and muscles, that it will improve our cardiovascular fitness if done regularly. It may improve how we walk, balance and climb stairs. It’s socially oriented, fun, and gets us outside and exercising. It’s easy on the joints of our legs as all the weight rests on our backside.

When cruising around on my bike, I notice things that I never have before: keen anglers at the local bait and tackle shop, and a dead bird on the side of the road. I haven’t joined a club, and haven’t bought lycra, but my weekly rides have become my special moment in time when I feel like a kid again. It makes me feel free and strong. As I pedal along the local wetland’s bike trail, I’m smiling for no particular reason, almost like flying.

• Do you have a story about the moment of discovery when a pastime became a passion? Send your essay of no more than 800 words to cif.australia@theguardian.com.