Why knowledge of physics would a runner?

Physics is very common in our lives, and of course this also applies to the performance of a runner.
For example, he or she needs to understand the air resistance when running, they may need to find a way to reduce the most air resistance that is against them so that they can show their best performance.
Or another example is they may need to find out the friction acting on between their feet and the track, they may need to adjust their training in different textures of running tracks, as each acts a different amount of friction.

Hello we have the same names lol.biology is the study of living beings , that is, all plants and animals including humans.

The answer is reflection.