By Jason Hidalgo
Gannett News Service

Whether you're a weekend warrior or have visions of competitive grandeur, an ill-fitting bike can set the wheels spinning for a bicycle-related injury, the American Physical Therapy Association warns.

Cara Gallas, a physical therapist with Biosport Mechanics in Reno, Nev., demonstrates proper bicycle fit. (Scott Sady/Reno Gazette-Journal)

Ensuring that you have a bike that fits you properly goes a long way in eliminating many of the aches and pains that can come with cycling. Here are some basic tips when getting a new bike.

Seat

Placement of your seat is a key factor for fit that also influences how you want to position other components such as the handlebars, said Dan Brown of Bicycle Bananas in Reno, Nev. As such, you'll want to adjust your seat first.

For biomechanical reasons, your seat should be high enough so your knees are at a 9- to 13-degree angle at the bottom of your pedaling stroke, said Kara Gallas, a Reno-based physical therapist with Biosport Mechanics. That way, the muscles involved are most efficient when firing.

Brown said a simple way to get within that range is to place your heel on a pedal, then pedal all the way down. Your leg should be straight with the knee locked at the bottom of the stroke. Once you switch from your heel to the balls of your feet, your knees should be within the proper angles.

Once you get the height right, you want to adjust your seat fore or aft to get the proper alignment. Using the previous heel trick, pedal all the way down again. You want your locked leg to be closely aligned to that bar that runs vertically from the seat post all the way down to the pedal.

Another thing to consider is the type of seat. Cut-out seats are now available that provide a nice compromise between the narrow seats that enthusiasts prefer and the more comfortable wide seats.

Handlebars

Compared with seat placement, handlebars are more subjective, largely determined by comfort or the type of riding that you do. When judging on comfort, make sure you listen to your body if the same aches and pains keep popping up.

Road bikes and mountain bikes have differences as far as handlebars, but the same general rules apply. First, determine if you prefer to ride high - that is, more upright - or ride low like a racer. Your riding style determines how close or far you want the handlebar to be to you or how short or long the bike frame should be. If you ride high, then the handle would be closer. If you ride low, then the handle would be farther forward.

When looking from the side, your knees should be about parallel to the handlebars at the top part of your pedaling stroke. When looking from the front, your hands and arms should be aligned with your shoulders and legs to form a box. This can be a problem with some mountain bikes that have handlebars that extend too far outward. That can be remedied by having a bike shop cut the handlebars for you.

Clearance

When you do a full stop during a bike ride, you usually get off your seat and stand up with the bike frame between your legs. Clearance refers to the distance between the top horizontal bar of the bike frame and the area between your legs.

For road bikes, you want to have a minimum clearance of 1 inch. Stops on mountain bikes are more spontaneous and require greater clearance, perhaps 3 to 4 inches of clearance.

Pedals

Another pedaling issue is foot placement. A common mistake is pedaling with the instep instead of the balls of the feet, which is bad form.

Toe clips and straps help by preventing your feet from going too far forward and helping keep them in the proper position. "Clipless" systems that work with cycling shoes tend to be more convenient.