This drill will help you improve your breaststroke arm stroke and make it more efficient. Keep one arm extended out in front of you without moving: try not to move it while you stroke with your other arm. Extend as far as possible during the catch phase of your single-arm stroke with your palm facing outwards at approximately 40°. Keep your arm extended at the beginning of the pull phase, pulling almost exclusively outwards with your hand until it is level with your shoulders. Bend your elbow and rotate your arm at the same time, so that your hand is facing inwards until it reaches your chest. It is important not to bend your wrist during this phase: it should simply be an extension of your forearm. Now begin the recovery phase of the stroke: move your hand under your chest so that it is closer to your other stationery hand trying to create as little water resistance as possible.