The launch of the London Cycle Hire scheme brings with it a whole package of socio-economic benefits and calisthenic good habits, not to mention the potential for firmer bottoms all round. A recent convert to two wheels myself, I can attest to (slightly) less wobbly thighs and a hint of upper arm definition. No one could possibly argue that cycling is bad for one's health.

But the amount of scrutiny, obscenity and casual lechery I have encountered on my bike in the past month has far surpassed the catcalls I suffered as a pedestrian. From the charming knight of the road who vocalised at length his desire to swap places with my bike (which, naturally, I was astride) to the zebra-crossing gallant whose actions spoke louder than words when he performed a gesture involving his fist, my bike and I have become the subject of a prurient interest more clunkily articulated than even the lorries we trundle past.

There is, I have since discovered, a near-fetishistic obsession with girls on bikes, with whole blogs and websites dedicated to cataloguing the very finest examples. It's as if cycling is some new means of drawing attention to oneself; in the eyes of male admirers, it's akin to wearing a short skirt with a plunging top – and it apparently means you're up for it. I'd understand the brouhaha if I was rolling through town on a carnival float in a grass skirt and carefully placed pasties. But more often than not, I'm wearing an old T-shirt covered in sweat.

It speaks volumes that this sort of behaviour wouldn't normally faze me in a certain context. A shrug of the shoulders, a roll of the eyes, maybe the blowing of a raspberry are the everyday choreography of the modern female existence: such attentions in bars and clubs are at least predictable, if not palatable. But in a recent survey of almost a thousand women, 87 per cent said they had been the subject of street harassment by the time they were 19. A further 66 per cent said it had begun at 16; 22 per cent had encountered pavement pervs at the age of 12. 12! They should be bombarding the public with water balloons, not cowering under a barrage of sexually offensive dogma spouted by priapic morons who can't walk to the shops without getting excited.

There is, however, something women can do about all this. The blog Hollabacknyc.com allows victims to get their own back on men who hassle by snapping them on a smartphone and uploading a description of the incident. This provides a forum for jocular phrases such as "asshats who can't keep it to themselves", but it's also a warning to those who think the hit-and-run nature of such offences means they won't get caught out. The crystal-clear photo of the "asshat" in question grabbing his crotch certainly provides embarrassment and entertainment; how far it will work as a deterrent remains to be seen. Readers, after all, are mostly women.

Hollabackldn.com has also just launched, which is good news for those of us who cycle in the capital. And plans are afoot for an iPhone app to make uploading and upbraiding offenders easier – though there's a delay over the question of the privacy rights of those pictured. Hmm. One might point out that the "Monday Morning Masturbator" caught mid-session on the underground by one contributor is clearly not the type to take umbrage about personal space and over-sharing.

One morning this week I decided to leave my bike behind. Walking in, I was reminded of how peaceful not standing out from the crowd can be. That is, until my posterior was violently grabbed and nearly wrenched off the end of my spine by a nonchalant-looking man in a suit. After all my proselytising about "hollering back", I was too thunderstruck to even shout and stamp my foot. Walking, it seems, is no safer than cycling.

Back on the bike, the jeers continue to flow in, leaving me more heartsore than saddle-sore. A more experienced rider than me recently advised actively seeking eye contact with drivers in order to assert my place on the road as a human being, rather than just another cyclist. Perhaps this is the sort of bullish approach that women need to take from day to day too.

h.walker@independent.co.uk