Passive shoulder range of motion is great, but what good is all the mobility in the world if you CAN'T USE IT or CONTROL IT?
Use a PVC pipe and work on controlling your end range shoulder elevation. This exercise looks easy, but trust me it’s a killer. Standing Y-wall slides with a lift off at the end is a great way to activate the serratus anterior and get in some low trap action; however, in standing, the Y lift off is perpendicular to gravity i.e. there's not much of a load on your low traps. When prone, gravity is now your WORST enemy. Thus, you'll really need to engage them. Throw in the fact that your at END RANGE and dealing with ACTIVE INSUFFICIENCY, and this exercise is no joke folks.
Some keys to remember:
- Ensure you have proper shoulder mobility first. This exercise should be PAIN FREE.
- You should be getting some extension at the thoracic spine, NOT THE LUMBAR SPINE. You shouldn't feel your low back working AT ALL.
- Think about pulling your scapula "DOWN and BACK". Think about pointing the inferior border of the scapula into the ground to cue posterior tilting.
- Don't shrug your shoulders up. Again, down and back is the cue.