The Effect of Bike Seat Models on Perineal Pressure During Cycling: Implications for Patients After Lower Genitourinary Reconstructive Surgery

Objective: To understand the effect of bicycle saddle shape and size on the pressure transmitted to the perineum, as prolonged perineal pressure and microtrauma amongst avid cyclists may increase the risk for complications following lower genitourinary surgery.

Methods: We tested five seats (Bontrager, Waterloo, WI) with varying levels of padding and morphology (comfort, fitness, fitness gel, race, and performance) for two different riders. The seats were installed on a Peloton stationary exercise bike (New York City, NY). Force measurements were performed using a 9833E-50 Large F-Socket Sensor (Tekscan, South Boston, MA). We measured total and perineal forces in three conditions at the same resistance: (a) at rest (not pedaling); (b) at 8mph; (c) at 15mph.

Results: Significant differences across the bicycle seats were observed with fitness gel seats providing the lowest perineal pressure. In all measurements, perineal forces were significantly lower at 15mph compared to 8mph (P < .001). When a rider used an oversized seat, less force was exerted compared to the appropriate size at both 8mph (P < .001) and 15mph (P < .001) speeds. Conversely, an undersized seat significantly increased perineal pressures at both 8mph (P = .018) and 15mph (P = .007).

Conclusion: Larger seats constructed of more impressionable materials absorb a greater total force and act to distribute the subject's weight thereby delivering less force to the perineum. More perineal pressure is delivered at lower speeds and at rest likely due to the cyclist lifting off the seat during times of strenuous activity.