Muscular & mechanical efficiency in cycling

In cycling some muscle coordination patterns result in high power outputs whereas others are more efficient. This study examined mechanical factors that affect muscle activity to identify coordination patterns used for different power outputs, total muscle activation and muscle activation effectiveness to produce power in cycling. Electromyography, pedal forces, kinematics, power output, cadence and slope were measured and compared indoors and/or outdoors in competitive cyclists at a range of resistances indoors and natural resistances during a time-trial outdoors. A trade-off existed between high power and high overall mechanical efficiency. Increased efficiency was dependent on the coordination of all muscles and independent of pedal force direction, while high power resulted from elevated activity of only a few muscles. Muscle coordination was influenced by workload and slope through altered power output or cadence. The study highlights the importance of specificity in cycling training to maximize exposure to competition specific muscle coordination patterns.