Modifications in saddle height affect the range of movement of the lower limb's joints during pedalling. Although its effect on movement patterns is poorly understood. The purpose of this study was to analyse the acute effects of small changes in bicycle saddle height on pedalling coordination and its variability. Lower extremity kinematic data were collected in random order for ten well-trained cyclists while pedalling at three different saddle heights: preferred, 2% higher and 2% lower than preferred position. A dynamical systems approach was used to quantify the coordination and its variability for selected joint couplings. Modifications in saddle height produced large changes in the frequency of movement patterns, although they were not enough to alter the coordination classification. Lowering the saddle height increased the frequency of the proximal coordinative hip-ankle pattern (F = 11.77, p < .01) and knee-ankle couplings (F = 14.39, p < .01), while decreasing inphase coordination (F > 11.03, p < .01) during the propulsive phase. Pedalling coordination variability was not affected, being greatest during the movement transitions and when the ankle joint was included in the coupling. This study demonstrated that pedalling pattern coordination and coordination variability were generally stable to acute small changes in saddle height in well-trained cyclists.
Keywords: Vector coding; bike fitting; kinematics; road cycling.