Multi-Location Analysis of Cycling Forces and Impulses Across Posture, Cadence, and Gear Ratio

This study aimed to investigate differences in forces and impulses at five rider–bicycle contacts (bilateral grips, saddle, and bilateral pedals) across posture, cadence, and gear ratio. In a randomized, repeated-measures laboratory design, 10 male and 10 female recreational cyclists completed 18 combinations of three seated postures, three cadences, and two gear ratios on a stationary indoor bicycle sensing system (50 Hz). Three-way repeated-measures ANOVAs with Holm correction examined body-mass-normalized vertical peak force, cycle-averaged force, and impulse per cycle at p < 0.05. Posture affected all three outcomes at both grips (p < 0.01, ηp2 = 0.360–0.552) but not the saddle or pedals (p = 0.821–1.000, ηp2 = 0.027–0.157). Cadence affected grip and saddle impulse and all pedal outcomes (p < 0.01, ηp2 = 0.544–0.908); higher cadence reduced impulse at all contacts and increased pedal-force magnitude. Heavy gear increased all pedal outcomes and reduced all grip and saddle outcomes compared with light gear (p < 0.001, ηp2 = 0.593–0.981). Interactions were limited, and sensitivity analyses reproduced all main-effect conclusions. Posture effects were concentrated at the handlebar, cadence primarily modified force-time characteristics and pedal-force magnitude, and gear ratio redistributed vertical loading between the pedals and other contacts. These findings support a purpose-dependent framework for region-specific mechanical load management in comparable indoor cycling conditions.