Most cycling injuries result from poor bicycle fit, bad technique, or bad riding position. Riding with bad form can lead to problems in the knees, arms, hands, and neck.

Here are some guidelines for finding a bike that is a proper fit for you:

1. Frame size: measure your inseam from the top of your inner thigh to the floor, with bare feet 6 inches apart. Multiply this number by .65. This number will give you the frame size as measured along the seat tube from the center of the crank axle to the center of the top tube. A mountain bike frame should be 2 to 3 inches smaller than your ideal road bike size. (To make dismounts quicker and easier).
2. Saddle Height- When you sit on your bike, your knee should be slightly bent at the bottom of the pedal stroke. Your hips should not rock in the saddle. A saddle that is too low will cause knee pain.
3. Fore/Aft saddle position- while seated on your bike drop a plumb line from just beneath your kneecap on your forward leg. The plumb line should bisect the pedal spindle on a road bike. On a mountain bike, the line should fall just behind the spindle.
4. Saddles and saddle tilt- there isn't any one saddle position that is recommended. Depending on your preferences you might want a level seat, a down nose tilt, or a slight up nose position. A slight nose down tilt lessens pressure and irritation. A slight nose up tilt helps some people to sit back on the seat. Women find narrow saddles more uncomfortable. Saddles come in many variations, such as gel saddles, saddles with shock absorbers, and saddles like the Terry saddle, that are wider.
5. Stem height- The handlebar stem height should place the stem about one inch below the tip of the saddle for most riding. For road races a lower position will provide a better aerodynamic position. For mountain biking, a position one or 2 inches below the saddle places more weight on the forward wheel so that it is easier to steer on climbs and less likely to pull up.
6. Arms and hands- the elbows should be slightly bent and relaxed. This will help absorb shock. Don't grip the handlebars too tightly. This will cause tension in the hands which in turn will create tension throughout the arms and shoulders. To avoid numbness in the hands, wear padded gloves.