No matter the activity there's an energy system that needs to be given attention in order to effectively perform. This energy system can be trained.
There's no limit or category distinction. It is all a matter of choice and commitment.
The Dynamic Resistance and Assistance Systems incorporate the stimulus of proprioceptors while training both muscle fiber and the entire motor unit which it is a part. The response to a nerve stimulus that is stressful and causes muscles to adapt together support my philosophy; resistance, and assistance with sufficient time over which it is applied go hand in hand to produce superior gains.