Repetition is the bedrock of martial arts training. Many in the martial arts and other sports refer to 'muscle memory.' MUSCLES DO NOT HAVE MEMORY. The reference to muscle memory is a way for people who don't know the 'why' of techniques or training to explain the why of techniques or training. It is a constant source of amusement when my work on understanding the why of techniques is derided and yet those same deriders then attempt to explain the why of the tactics and techniques they are teaching. The why explanation that is anecdotal at best.
The brain is 'plastic.' Neuroplasticity refers to the ability of the brain to create new neuroconnections throughout its life. Habits are well established neuroconnections. If you want to create new habits, you need to create new neuroconnections. You then need to reinforce them with repetition.
The brain changes physically (anatomy) and functionally (physiologically). It's not just about 'the way we think.' Training is about changing the physical and functional characteristics of the brain.
Your training is developing new neuroconnections and reinforcing those neuroconnections. That is why visualisation works to improve your physical performance. The brain changes itself. You visualise your physical activity and that is establishing and reinforcing those new neuralconnections. There have been studies done were people how have never played an instrument have learnt to play that instrument without physically playing it.
There is training that trains the body - pushups, etc - however, the skill training, while you may think it is physical training, is actually mind training.