Once the conversion from food (chemical potential) energy into motion (mechanical energy) takes place, the cyclist can put this mechanical energy to use. The cyclist does not directly do work on the pavement to make the bicycle go forward. Instead, the cyclist is attached (coupled) to the bicycle which is a complex machine.

The cyclist applies a force to the pedals, pushing them around in a circle. The pedals are attached to a crank that applies torque to the front chainring. The chain then pulls on the sprockets on the rear wheel which causes the wheel to turn. The cyclist can choose from a variety of gears depending on the riding condition at the moment.

-more to come