I spent some time with a patient this week who was suffering from shoulder impingement. They were trying to start a workout program to strengthen the shoulder. They were performing upright rows in sets of 3 at 12 reps per set. I had to add some additional information to make this the correct exercise for their condition. A better example would be to perform eccentric (negative) sets of 4 with reps of 6-8 per set. This allows the patient to train more for strength/endurance without an increase in muscle size (hypertrophy). In this particular case, an increase in the size of the supraspinatus would only increase the effects of impingement. It is often a good idea to remind your trainer of injuries that you may have. They can often adapt your program to fit your needs. Stay healthy!
Christian
