Shoulder impingement syndrome is a common shoulder injury in active adults. Generally speaking, muscles surround bone; however, the shoulder is different. Bone surrounds muscles in the shoulder. Reach across your body and tap your shoulder. You are tapping the bone that exists under the skin. Directly beneath that bone is the rotator cuff, which is a group of muscles and tendons that allow the shoulder to move the way that it does. Shoulder impingement occurs when those muscles and/or tendons become trapped or compressed during shoulder elevation. The result is pain, and if it is not treated, damage such as tearing can occur to the rotator cuff. Most patients with this shoulder impingement syndrome can be successfully treated with medication, stretching exercises, and avoiding repetitive overhead activity.
Because extending the arm up and over the head aggravates the condition, exercises that require a person to elevate the arm in that way should be be avoided. Swimming should be avoided, as the various swimming strokes require arms to extend up and in front of (over) the head. Weight lifting can be done, so long as no particular lift requires the overhead arm motion. Any overhead team sport should be avoided, so things like baseball, softball, tennis, racquetball, etc. should not be done. As for daily exercise and chores, painting should be avoided.