Treading water

Swimming style

Treading water or water treading is what a swimmer can do while in a vertical position to keep their head above the surface of the water, while not providing sufficient directional thrust to overcome inertia and propel the swimmer in any specific direction. As it expends less energy than traditional strokes, it is often used by swimmers to rest in between periods of exertion without having to leave the water.

This keyword could refer to multiple things. Here are some suggestions: