Originally Posted by PedOncoDoc

The term "muscle memory" is a bit misleading as there is no "memory" in the muscle itself. The information from the muscles, tendons and ligaments about stretch, contraction, position and movement are all relayed to and processed by the brain. Through repetition, a repeated action can take less and less conscious effort although all of the signals are still being processed and controlled by the brain. When someone talks about muscle memory, they mean an action they can perform at will without significant conscious effort. When a movement is learned to this level, altering the movement feels "off" due to subconscious expectations of signals that should be received.

Walking is a wonderful example of "muscle memory" - we all had to learn to walk as toddlers and, after much practice, we don't have to actively focus on which foot to put forward and when, how far to lean forward, how long our stride should be, when to pick up the back foot, etc.

My $.02...anyone else have any other thoughts?