Duration: 15 minutes
Swimmer's shoulder (impingement and rotator-cuff irritation) is by far the most common swimming injury, driven by the internally-rotated, forward-reaching nature of the stroke.
This routine strengthens the rotator cuff and the muscles that control your shoulder blade, and opens the front of the shoulder, to keep the joint balanced and healthy. It needs only a resistance band and the floor.
Keep the load light and the reps high. This is control and endurance work, not heavy lifting. Do it once or twice a week; it also makes a great pre-swim warm-up.