The effects of muscle size on the efficiency of muscle contraction

Skeletal muscles are typically assumed to behave as single fibres scaled to larger sizes without considering the mechanical effects of greater tissue mass. While previous work has shown that larger muscle size and mass decreases the work and power output of contracting muscle, the metabolic consequences of these factors are still unknown. In this study we show that muscle efficiency decreases with increases in muscle size, and this effect is more pronounced for slower muscle fibre-types and at lower muscle activations.