'You cycle to work? You must be mad," used to be the reaction when I told people about my commute. Today, especially in London, cycling to work is at last becoming "normal": it is no longer the reserve of Lycra-clad men.
Joining the swarm of cyclists travelling south towards central London from Islington in the morning, I feel like I could be in Amsterdam or Copenhagen - where cycling accounts for a third of all trips. But in the UK, we still have a long way to go. Just 3% of commuters here cycle, with around 4 million people still driving less than three miles to work - a 20-minute bike ride each way. If all of these people swapped their cars for bikes it would save around 1m tonnes of CO2 a year.
As a member of parliament, my four-mile round commute to Westminster takes under half an hour (with the trip back, uphill after the 10 o'clock vote, taking a bit longer). It is by far the quickest way to get to the House of Commons. In fact, most traffic in London moves at the same speed it did a century ago - barely 10mph. On a bike you can easily keep up with or beat that speed.
If it's so easy and so quick - why aren't more of us commuting by bike? Here are some of the common myths that people claim prevent them.
1. "But won't I be killed?"
The Department for Transport's own statistics show that, over the last three years, cycling is - per mile travelled - safer than walking. Indeed, the more people who cycle, the safer it becomes, because drivers get used to seeing cyclists on the road. As more people have taken to their bikes in London, so there has been a 50% drop in cycling casualties per mile ridden since the mid 1990s.
We all need regular exercise and the truth is that most people do not get enough. Cycling is much more convenient than joining a gym or going swimming, and is a regular exercise that can be slotted fairly easily into most of our lives. I discovered in February that I have the cardiovascular fitness of someone almost 20 years younger.
2. "Don't I need lots of gear?"
All you need is a bike, a lock and some lights. With a few outstanding exceptions, Lycra really doesn't do justice to the figures of most people over 30. If you feel most comfortable wearing a suit, then wear one and cycle slowly. You are going to work, not climbing Mont Ventoux.
Helmets aren't compulsory and their benefit isn't proven outright. Indeed, recent evidence suggests that wearing a helmet may encourage drivers to overtake more closely - putting you at greater risk.
3. "Won't my bike get stolen?"
A good lock and a secure area to park your bike will help. More enlightened employers will often provide the latter. Forming a bicycle user group in your workplace can improve your chances of obtaining decent facilities.
Most police forces have started offering people bike registration schemes. They'll be able to enter details of your bike onto a database - this will help to recover it if it's stolen.
4. "I haven't done it for years"
The government recently launched Bikeability, a series of three levels of cycle competency, which teaches children the skills and confidence to ride on the road. Local authorities - especially those in London - now offer a free or heavily subsidised adult version of Bikeability.
Even if you think you are a good cyclist, professional cycle training will greatly help boost your confidence and can provide tips and skills to staying safe. I've had cycle training myself and, even though I felt very confident beforehand, I'm certainly a better cyclist because of it.
5. "The weather in Britain is too bad"
In many cities in northern Europe, up to 30% of all journeys are taken by bike - often in places with wetter, colder weather than the UK. Some cities in this country have similar levels of bike-friendliness; a quarter of commuters in parts of York, Cambridge, Oxford and Hull cycle to work.
In my city, Transport for London claims that the average cycle commuter will only be caught in the rain 12 times in the average year. This is, as any cyclist will tell you, quite obviously a lie - but you'd be surprised how infrequently it actually does rain. My policy is - if it rains, the bike stays at home. No one wants their MP turning up looking like a drowned rat.
6. "I live in a hilly area"
You can't tackle hills without gears. The worse the hill, the more serious the gears needed. But, frankly, no one is going to blame you if you get off and push. And then you've got a free-wheel downhill.
7. "There's too much pollution"
Pollution levels for cyclists are lower than you might think - on hot days when pollution levels are highest, cyclists are exposed to less pollution than commuters sitting in their cars.
8. "Bikes are expensive"
There's now a tax incentive, which means that you could buy a bike for a substantial discount through your employer. Find out about the scheme here: tinyurl.com/zob7l
9. "I can't carry anything on a bike"
Some people have moved house by bike, and transported furniture - even pianos - by bike. Modern panniers are adapted for files and laptops. You can buy huge panniers and removable baskets that can carry shopping - and even David Cameron's shoes!
10. "There are other reasons"
No there aren't. Get on a bike and give it a week. Chances are you'll soon join the ranks of converted cycle commuters: green, healthy and just a bit smug.
· Emily Thornberry is MP for Islington South and Finsbury, and chairwoman of the all-party parliamentary cycling group
