Bicycle seat designs and their effect on pelvic angle, trunk angle, and comfort

To examine whether bicycle seats with anterior-medial cutouts influence pelvic angle, trunk angle, and comfort in female subjects during cycling.

Twenty female cyclists pedaled a stationary bicycle with their hands on the tops and drops of the handlebars under three different saddle conditions (standard, partial, and complete cutout designs). Pelvic angle was measured using an inclinometer attached to a caliper whereas trunk angle was quantified from digitization of video images. Comfort level was assessed subjectively by having participants rank the saddles from most to least comfortable.

Anterior pelvic tilt angles for the partial and complete cutout saddles were 8% and 16% greater, respectively, than values for the standard saddle condition ( P < 0.05). Trunk flexion angles were greater for the complete versus standard and partial cutout designs ( P< 0.05). Participants displayed a 77% greater anterior pelvic tilt angle and an 11% greater trunk flexion angle in the drop versus top handlebar positions ( P < 0.05). A total of 55% of the subjects ranked the partial cutout saddle as the most comfortable, and 30% ranked the standard saddle as the most comfortable.

These data indicate that partial and complete cutout saddle designs may increase anterior pelvic tilt, and saddles with a complete cutout design may increase trunk flexion angles under select cycling conditions. A saddle with a partial cutout design may be more comfortable than a standard or complete cutout saddle design.