When I was a graduate student of Physical Education, learning numerous skills of different sport was a daily affair. As I was basically a runner and running is a cyclic movement and don’t involve complex & discrete movements, I was quite un-coordinated at the beginning. It is not also possible to practice all the skills all the time. Still I managed to learn so many skills. Thanks to Imagery. Imagery helped me a lot in learning & correction of skills.
You can practice imagery thousand times-a-day without actually involving in any physical movement. But Imagery do involve with our physiological system. It may increase or decrease your heart beat, respiration.
I also believe many people does imagery without knowing about it as psychological skill training. People naturally do it, as I did.