Architectural and Force-Producing Characteristics of Knee Extensor Muscles Between Alpine Skiers and Road Cyclists

Abstract

Han, T-G and Lee, H-D. Architectural and force-producing characteristics of knee extensor muscles between alpine skiers and road cyclists. J Strength Cond Res XX(X): 000–000, 2026—This study aimed to investigate whether muscle architecture and torque characteristics differ among athletes subjected to different sport-specific loading conditions. Alpine skiers (AS; n = 9, predominantly eccentric [ECC]-loading exposure) and road cyclists (RC; n = 9, predominantly concentric [CON]-loading exposure) were recruited. Muscle architecture (fascicle length, pennation angle, and thickness) of the vastus lateralis (VL) was measured at rest using ultrasonography at 10° and 100° of knee flexion. Maximum voluntary isometric (ISO) knee-extension torque was measured at 40°, 60°, 80°, and 100° of knee flexion, from which the optimum joint angle and peak ISO torque were estimated. Peak knee-extension torque was measured during CON and ECC contractions over a knee-flexion range of 0°–110° at 30°/s and 150°/s. Statistical significance was set at p < 0.05. Among the architectural variables, RC exhibited greater VL thickness than AS at 10° of knee flexion, whereas fascicle length and pennation angle did not differ between groups. Compared with RC, AS showed significantly greater ISO knee-extension torque at 100° ( p < 0.05). The estimated optimum joint angle was also greater in AS ( p < 0.05). Absolute ECC peak torque did not differ significantly between groups; however, AS demonstrated greater ECC torque when values were normalized to the estimated peak ISO torque. These findings show that AS and RC demonstrate different knee-extensor torque-angle and torque-velocity characteristics despite similar VL fascicle length and pennation angle. They further indicate that knee-extensor force-producing characteristics may be shaped by the dominant loading and contraction-mode demands repeatedly experienced in each sport.