Well, I certainly applaud anyone wanting to cycle in a polluted city, but take it from this old cycling rat, I've spent my entire adult life on the bike, and an activity like this one can do more harm than good.

If you only cycle in polluted areas (and that's all a single city is going to provide for you), you're setting yourself up for injuries down the road. I've seen it a hundred times.

It's like putting shitty filters in a stock Toyota Tercel. What will you accomplish? You'll blow out the fuel system, the air filtration, the vents, etc., because those factory parts aren't designed to handle the byproducts of intake much more toxic than the factory installed filters.

Polluted bike rides basically only train the legs and to some extent, the thighs. What you really want to do is train your entire body, all the major muscle groups (chest, back, abdomen, legs, shoulders and arms) at the same time, over the course of a bike ride. And don't forget your cardiovascular work! I'm proud of you guys wanting to do this. Three cheers! Falling in love with exercise, eating right, etc., is one of the greatest things you can do for yourself. And you WILL fall in love with it if you can just force yourself to stick with it a year or two and experience the amazing progress you'll make. But do it right, okay?

My advice, find a good city, with clean air that won't poison you (especially in the beginning, until you build up a resistance) and guide you in your quest for physical fitness. Thirty to 45 minutes a day, three days a week, is all you'll ever need to do (I refuse to believe anyone is so busy that he or she cannot make time for that, especially considering how important it is).

And don't worry about being embarrassed or not being in shape the first time you ride your bike. You have to start somewhere and almost every one of us were there ourselves at one time. So no one will say anything to you and very, very quickly you will progress way beyond that stage anyway.

Now get out there and do it! :-)