Forget the aesthetics of fashion: In cycling a bespoke fitting prevents injury—to your back, ankles, knees, and hips. "Cycling is a repetitive motion," says Zane Castro, a fit specialist at Jack & Adam's Bicycles in Austin. "If you practice poor movements, you can injure yourself quickly." Many shops now staff exercise scientists who help cyclists improve biomechanics by straightening the alignment of their feet, knees, and hips to fully harness the body's potential. Premium fit sessions ($150 to $300) usually begin with body measurements and progress to an on-bike analysis complete with video. "People have a difficult time self-diagnosing—that's why we visit therapists and also why cyclists need fit specialists," says Brady Gibney of Cadence Cycling & Multisport Center in Philadelphia.