I was reading some tips on swimming strokes and the importance of form. One of the tips was on keeping your elbows up on the stroke recovery for freestyle. Along with this is bending your elbows instead of simply swinging your arms high over your head.
It is important to do this for two reasons. One is simply that it is more efficient. Second, and perhaps more importantly, is that this allows your hand to enter the water first. This allows you to start the next stroke immediately and catch water. This immediate “catch” allows you to get more power out of your stroke as you start.
Hope this helps.by