Smiles per hour. That’s the cost of riding bikes. If you’ve ridden a bike, you’ve probably had the experience of traveling farther on two wheels compared to how far you would go on two feet. When you pedal forward you are multiplying the distance your feet can travel. For example, taking a step only gets you as far as your foot can reach, but a bicycle can coast along a flat surface with relatively little resistance to motion. Pretty cool and highly efficient.