Keep your arms completely relaxed during the recovery phase of your stroke and “swing” them up overhead (not wide out to the side) and let them slap the water at which point you’ll quickly drive your arm down into the water in order to keep your turnover up. High swingers will feel sloppy and messy and “rushed” and that’s what it should feel like. It is a drill designed to get turnover up and eliminate any pause or deceleration a swimmer has in his or her recovery. It also forces more shoulder roll. It’s good to do some of this before doing some sprinting.