Over the years I've worked with many people with shoulders issues including separated shoulders, dislocated shoulders, broken collar bones, thoracic outlet syndrome, shoulder impingement syndrome and even someone with a rare virus in a nerve running through the shoulder. Here's a link to an amazing explanation of shoulder bio=mechanics by Dr. Clay Hyght titled "Shoulder Imgpingment Syndrome".
All of these people needed to do some work balancing out their upper body muscular to deal with the underlying cause of continued pain and biomechanical issues. BUT everyone should be paying to their upper body structural balance in their training programs, anyone who works at a desk in particular. 95% of population have similar upper body structural balance issues.
All too often I get new clients who's back muscles are almost amnesic. They can't fire their back muscles and their scapular stabilizers in particular. Their brain can't send the signal to their muscles to fire AKA neural pathways. If you don't know what scapular stabilizers are then chances are yours are also amnesic.
Here are some VERY simple tips for improving structural balance in the upper body. Most people need hands on help to ensure form and technique are correct. If you don't want to end up with a surprise shoulder issue or neck pain, then these are tips are essential:
1) Fix your desk set up. The book I co-authored in 2006 titled "Working on the Ball: A Simple Guide to Office Fitness" has some very simple and relatively inexpensive tips for improving your desk set up without the help of an ergonomist. I you're working on a lap top, you MUST get a proper mouse and likely a key board tray and full size key board to get on the right track with your upper body posture.
2) NEVER NEVER NEVER do more chest work than back work. Push ups are included here. Don't even think about lifting heavy on the chest until you get your scapular stablizers going. You are only going to make your structural balance worse.
3) Always do a pull movement in your workouts. Anyone starting into strength work should have a chest to back work ratio of 1:2 or even 1:3. Always do twice as many back exercises as chest exercises.
4) Always include rotator cuff exercises in your weekly training. If you only have time for one rotator cuff exercise then do external rotation. My fave is a really stable side lying external rotation with a really light weight. If you don't feel a hot poker sensation in the back on the shoulder joint, then you're not getting it right.
5) Do a proper chest stretch and neck stretch once a day. My fave chest stretch is lying back over a stability with your shoulder blades resting on the highest part of the ball, arms out to the side.
6) If you're doing a back exercise and you don't feel it in your back then you're not working your back! Likely you're over strengthening the exact wrong muscles like your upper traps. Yikes. Big problem.
7) Don't hire a trainer who doesn't pay really close attention to upper body biomechanics. He/she should be paying very close attention to whether or not you're feeling back exercises in your back muscles.
8) Always include a mid to lower trap exercise in your strength training program. What are these exercises? The YTW shoulder prehab/rehab set will get in there if your form is bang on. You will have to lift no weight or really light weights to start.
9) Don't do heavy overhead press movements until your shoulder stabilizers and back are better balanced in relation to your chest. If you have any clicking or pain in your shoulder in overhead press then you are heading down a dangerous road my friend.
10)Anyone treating you for an injury should be prescribing stretches and/or exercises for you to do when you're not with them. There should be a plan of attack and you should be included in helping yourself. Stay away from therapists who just treat without giving you additional homework.
Those are some very very simple tips. Shoulder rehab is complex. Never self diagnose please. Don't ask a personal trainer for a diagnosis including me. Don't self diagnose over the internet. Don't ignore any pain that gets worse over time.
Call my of the peeps at Athlete's Care King and Yonge (416)368.9990 (Mike or Jimmy or Kate) or Davor or Mike at Mount Sinai Physio Clinic (416)619.5546. They are chiros who practice Integrated Functional Therapy.
And remember once a shoulder goes, it's a lot of work to fix.