Yet your body learned this skill by itself, applying its own wisdom. Many involuntary processes, controlled by WOB support any voluntary task that you do. Imagining the task. Execution by the WOB Touching your nose requires even more than muscle coordination. The brain controls muscles.
Control requires energy that is supplied by the blood.
By touching your nose you actually increased brain blood flow. What an idea. Suppose that one of your older relatives suffers from a so-called Alzheimer disease that results from low blood perfusion of his brain. His nose, or his body and so increase his brain blood flow. Obviously, muscular effort involved in touching is meager, and so is brain blood perfusion.