Originally Posted by
luderart
No. Actually it's quite cold. But while riding with my usual jacket to keep warm, I sweat due to the effort involved. And so the sweat gets trapped in the jacket. And anyway, maybe I can ride with a lighter jacket. But I don't want to catch a cold.
By the way, how did you know I am from the Middle East?
Depending on how cold the conditions you're riding in, you might try the winter biking forum as well. This is a common dilemma for winter cyclists - you want something that will block the wind, but you want something "breathable" - ie, let's the water vapor from sweating out through the jacket. Unfortunately, all my suggestions are for expensive jackets meant for well below freezing riding.
What's temperatures are you riding at?
Certain materials are not "breathable" at all - cheaper waterproof material, whether it's a rain jacket or a winter jacket, is almost never breathable whatsoever. Only the rather high end waterproof jackets are, and sometimes they still aren't breathable enough, depending on which one you're looking at. Fleece is usually breathable, there's also more specialized fabric.
One thing to keep in mind is that while biking, you're body is generating heat, so you don't need quite as much insulation. However, if you're only biking 3 km and you're having trouble and sweating a lot, but you do the ride regularly, my first thought is that there must be something wrong with your bike. The first thing, as other people have mentioned, is the seat height. After that, try picking up the front of the bike and spinning the wheel - it should rotate freely at least 10 times. Do the same with the back wheel. If it comes to a stop on it's own before 10 rotations, there may simply be something wrong with the wheel - perhaps the brake is rubbing against it? That can kill your ability to get anywhere without a lot of work...