Intra-limb coordinative adaptations in cycling

This study aimed to establish the nature of lower extremity intra-limb coordination variability in cycling and to investigate the coordinative adaptations that occur in response to changes in cadence and work rate. Six trained and six untrained males performed nine pedalling bouts on a cycle ergometer at various cadences and work rates (60, 90, and 120 revolutions per minute (rpm) at 120, 210, and 300 W). Three-dimensional kinematic data were collected and flexion/extension angles of the ankle, knee, and hip joints were subsequently calculated. These data were used to determine two intra-limb joint couplings [hip flexion/extension–knee flexion/extension (HK) and knee flexion/extension–ankle plantar-flexion/dorsi-flexion (KA)], which were analysed using continuous relative phase analysis. Trained participants displayed significantly (p < 0.05) lower coordination variability (6.6 ± 4.0°) than untrained participants (9.2 ± 4.7°). For the trained subjects, the KA coupling displayed significantly more in-phase motion in the 120 rpm (19.2 ± 12.3°) than the 60 (30 ± 7.1°) or 90 rpm (33.1 ± 7.4°) trials and the HK coupling displayed significantly more in-phase motion in the 90 (33.3 ± 3.4°) and 120 rpm (27.9 ± 13.6°) than in the 60 rpm trial (36.4 ± 3.5°). The results of this study suggest that variability may be detrimental to performance and that a higher cadence is beneficial. However, further study of on-road cycling is necessary before any recommendations can be made.