>>1950936Very obviously your body, your legs and ass have an optimum for power delivery, force production and endurance.
Suppose you pushed on the pedal of a bike that was geared arbitarily high. You'd produce the maximum of force you are capable of producing but you can not do so for long and, unless you're able to produce more force, you wont get that thing spinning and thus power output will remain low.
Suppose the opposite: The gearing is arbitarily low. Your muscles can only produce force up to a certain speed. In fact you can only produce that maximum force determined in the first thought experiment up to a certain speed, after ehich it will drop. Also when spinning out you're utilizing alot of power merely to reverse the momentum in your legs.
At last on a bike with sensible gearing you'll be able to produce a force far from your physiological maximum but one that your fatigue resistant muscle fibers alone can peoduce. You'll be able to produce this force for possibly many revolutions per unit of time, thus increasing power, without wasting too much power on reversing the motion of your legs.
Now if the gradient shifts or wind changes your effective gear ratio changes. Which is why you want to be able to change gears.
You should, when riding, aim to be riding at a cadence at which you can produce the highest power possible, for indefinately long. Choose the gear accordingly. Do not mash unless specifically wanting to do so and understanding why. Also do not spin out, which you wont do, no one volutarely spins out.
