It is a fight inside. You and your body that follows your will to a certain extent but not quite.
An Element so soft that you have to apply delicate technique to move at intended pace.
The muscels relaxing instead of hardnening in other sports. Relaxing until the get all wobbely and blend into the background.
I participated in sports most of my life. Many many different sports but I never swam competitively. I never really examined the sport from a competitors POV until my daughters started competing. And I'm thinking, Man, that water is a killer, you have to push an entire pool full of water out of the way in order to move forward, then it rushes back again and fills the void you just made and attempted to travel through. Then, if that's not bad enough, for more than half the time, while you're pushing the pool full of water out of the way and quickly squeeze into that little space you made in the water ... you can't breathe. Your head is underwater. When your head is finally clear from the water, every breath is filled with water. It is a tough sport.