Lets be serious for amoment, its all to dowith how the body reacts to the biomechanical chain of events taking place subsciously inthe peripheral senses, as the shoulder arm extend it triggers a response to the abdominal wall to contract to protect the spinal column and head from to much over rotation in other words protect the spine from injury.Everything has a purpose the body works all or nothing.The big toe has a major part to play in this process.