Watch how this forward recovery snaps the hips back into line. When...

When the arms shoot forward, the whole body can be driven forward with them.
In short breaststroke races, there is no time to wait for the hips to get back into line.
That shortens the time spent in a high-drag position and lets swimmers use higher rates without sacrificing the line.
From underwater, watch how quickly the hips snap up when the swimmer drives forward.
What do swimmers need to be able to DO, at every level?
What sets can they perform?
How do those sets reflect the necessary fitness?