AVERAGE JOINT POWER DURING MAXIMAL CYCLING

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Power produced at the ankle, knee, and hip during submaximal cycling at pedaling rates of 40 to 100rpm has been reported to account for approximately 20, 45, and 35% of total power delivered to the cranks. Joint power produced during maximal cycling has not been reported and it is unclear if the relative contribution of power from each joint would be similar to that during submaximal cycling. PURPOSE: To determine the relative contribution of ankle, knee, and hip power to maximal cycling power across a large range of pedaling rates. METHODS: Five well trained male cyclist (76 ± 5kg) performed 3 maximal intertial-load cycling trials during which pedaling rates ranged from 68 to 190 rpm. Pedal forces and pedal and crank position were measured at a frequency of 200Hz. Two dimensional leg kinematics were determined by the geometric relationships of a five-bar linkage. Net joint moments at the ankle, knee, and hip were determined using inverse dynamic techniques. Joint power was calculated as the product of joint moment and joint angular velocity and averaged over each complete revolution of the cranks. RESULTS: Average crank power (right leg only) increased from 612 ± 46watts at 68rpm to 669 ± 41watts at 106rpm and then decreased to 272 ± 44watts at 190rpm. Average ankle power accounted for approximately 21% of crank power at pedaling rates of 68 to 156rpm and decreased to 11% of crank power at 190rpm. Average knee power accounted for approximately 56% of crank power from pedaling rates of 68 to 156rpm and decreased to 48% of crank power at 190rpm. Average hip power accounted for approximately 23% of crank power at pedaling rates of 68 to 156rpm and increased to 41% at 179rpm. CONCLUSION: The relative contribution of ankle, knee, and hip power during maximal cycling were similar to those reported for submaximal cycling and were stable across a range of pedaling rates. That similarity suggests that cyclists use a single strategy to produce maximal and submaximal power. At pedaling rates above 156rpm the proportion of power produced at the hip joint increased sharply whereas the proportion of power produced at the ankle and knee decreased.