A: Single-arm drills are the best way to focus on every phase of the stroke, including the pull. The non-swimming arm should be kept at your side to allow and promote torso rotation while performing the drills. The basic version is with no equipment. Start with 6×25, alternating arms each 25. A more advanced single-arm drill is performed with a paddle to provide a bigger surface area during the pull. While the focus is on the pull during these drills, don’t forget to rotate your torso enough that your non-stroking shoulder pops out of the water.