Once a minority sport for super-greens and fitness fanatics; these days everyone seems to be cycling. Bike rails have never been busier. Even if you’re not saddling up yourself, chances are you’ve noticed how many others are. In the aftermath of the terrorist attacks on the Tube a year ago London’s bike traffic rose by 20 per cent, says Transport for London (TfL).

And it’s not just a city trend: the National Cycle Network says there was a 15 per cent rise last year in total bike traffic in the UK. Even politicians, rarely known for trendsetting, are taking up two wheels. Boris Johnson and David Cameron have attracted the most attention. And this week the Government announced that it is ploughing an extra £15 million over three years into bicycle training for children and more cycle paths. Something for which Ken Livingstone, the Mayor of London, has campaigned hard.

I, too, have done my bit. A few months ago, sick of being a bleary-eyed Tube creature, I transformed into one of London’s commuter cyclists. My journey takes 45 minutes each way, frightening and thrilling in equal measures. I should add — since it is something that hardcore cyclists never fail to point out to me — that I don’t do it every day. I take a day or two off every week, which I see as risk reduction.

The fact that 72 per cent more people cycle in London today than in 2000 is a triumph for this green, healthy way to get around. But in our haste to hit the pedals, have we forgotten to do our homework? It’s a serious thing, cycling.

I leapt on to my sister’s old school bike, bought second-hand in 1993, with hardly a thought of the consequences. As a result, I’ve a dull ache in my lower back which kicks in a few hours after I cycle. Also by my bike: we’ve never been ideally suited. It’s heavy and I curse the brute every time I lug it up the stairs to my flat. Worse still, the brakes are on the blink and the seat is held together with masking tape.

In need of guidance, I turn to Mosquito Bikes, the shop-cum-repair centre in North London. Just being there I sense that I am part of an urban bike clique. Checked in for what the owner Roger Graver calls a size-cycle fitting, this two-and-a-half hour going-over, from helmet tip to toe, introduces appropriate gravitas to the sport. The point, Graver says, is to make being on your bike as comfortable and energy-efficient as possible. Then you’ll spend more time on it.

First up is my cyclist’s profile. A template is created for what kind of cyclist I am, based on my cycling history, physical measurements and flexibility. It all goes on the computer so I can either alter my existing bike or buy a new one suited to my exact needs. The crème de la crème option is to splash out on a custom-made frame, from £650, which, sadly, isn’t an option for me.

Graver has a professional, if unlikely, interest in my feet. He says that most people don’t realise what an important role they play, affecting how efficiently you pedal. “The arch of your foot collapses, or pronates, when you push down,” he says, measuring mine with one of those measuring devices you find in children’s shoe shops. “You want a shoe with a rigid sole that decreases the amount of pronation so you cycle efficiently. Use the ball of your foot to push down as it carries the most power from your body.”

Then it’s time to sort out my on-bike posture to get to the bottom of my back pain. It doesn’t take long. I imitate how I cycle and become the laughing stock of the shop. “Look at the way she’s holding on to the handlebars with her fingertips,” one of the assistants mutters. “Why are you trying to sit bolt upright?” snaps Graver. I say that I’m trying to keep my back straight. There lies my error. “Unless you’ve got a serious injury, your spine. with its natural curve, copes with crouching fine,” he says. “It is worse to compensate by trying to cycling one-handed to stretch it out. It’s rubbish that this gives your back a break from crouching over; it strains it. You should use the same core stomach muscles as when you stand up from a chair. You lean forward with your back relaxed, shoulders down, and tighten your stomach muscles to support you. Hold on to the handlebars properly.”

I surrender to this position, elbows slightly bent, and notice how much less hunched I am. By way of punishment, I am launched on to the shop’s mechanical adjustable bike. It’s a bit like one of those exercise machines on which you pedal fast but never get farther than your living room. After 20 gruelling minutes, Graver has taken several pictures of me with a camera to illustrate my improved position.

I learn about “cadence”, the number of pedal revolutions per minute. Careful use of the gears enables you to keep it constant, lessening the strain on your knees (between 70rpm and 90rpm is ideal). As far as changes to my existing bike, there isn’t much to do as it’s mostly me that’s at fault. I could do with lowering my seat a bit. Contrary to belief, there is an optimum height. It depends not on how tall you are but how flexible and what you’re using your bike for. In city traffic, the tip of your foot should be able to touch the ground when you’re seated on the bike. For an accurate measurement, you’ll need to pop into a bike shop.

In the joyful event that I ever upgrade my wheels, Graver suggests that I stick with a hybrid model (half racing bike, half mountain bike) avoiding drop handlebars as they keep you low, looking straight ahead. As a novice to city traffic, it’s better to have good peripheral vision.

Fearing seduction by one of the latest and unbelievably light models, made from carbonfibre, and costing upwards of £5,000, I speed off to work. It’s a relief to give in to the natural position that my body forms, rather than fighting it. By the end of the day, I’ve yet to feel a single back twinge. Could this be a turning point for me and my bike? I don’t promise to be raiding Lycra shops any time soon, but our relationship is on the up.

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