Everybody is talking about the trouble of an unstable back foot (as you can see in the clip!)

It all goes back to the Natural Motor Preferences of the individual! 

Most pitchers are taught to put their back foot parallel with the rubber, but unfortunately, a human body is not built to do so!

It looks like the pitcher in the clip is an Anterior Muscle dominant athlete, which means his foot and upper leg will rotate parallel and his lower leg rotates in opposite direction (the so-called Corkscrew)

So when this pitcher is taught to keep his back foot parralel to the rubber, the body needs to find a way to get that Corkscrew going, because the foot is anchored in the ground it can’t slide —> Foot seems to be unstable! (This is knee injury creator)

This is all caused because the coaches had no idea about the individual motor preferences of the individual.

Solution: AM Chain pitchers need to have a foot in angle with toes towards rubber in order to get effective, healthy, energy-saving lower body movement. And you will NOT see any so-called unstable back feet anymore

PS: This is NOT the same with Posterior Muscle Chain Athletes!!!