help w/ shoulder pain from swimming

Hard to say....why not post a swim video?

Swimming causing pain is not good and things can get worse so address it now.

I agree with dace.  More than likely you're crossing over the center line of your shoulders as you begin to place your arm in the water.  When your arms are beginning to extend from your shoulders your arms should hit the water directly in front of the shoulder joint.  They should not cross over toward your head or they certainly shouldn't cross to the other side of the body.

You should also have some rotation of your shoulders (left shoulder to right shoulder) so that one side drops toward the bottom of the pool and the other is raised out of the water to allow the rotation within the shoulder joint to be in a neutral position.  This will allow your joints to feel much less stress and greatly reduce the chance of injury.

Lastly is hand position.  When you place your hand in the water it should be flat with the surface of the water.  No turning of the hand is needed.  If you are rotating your thumb downward to "slice" the water you're only causing your shoulder to rotate into a position that is more prone to injury.

Article about reducing shoulder injuries.

Also there is a downloadable file that will help you see what a proper swim stroke should look like at Mr. swim smooth.  Take a look at it and try to determine where your flaws seem to be.  A video will certainly prove extremely beneficial!  You can post it here to and others may be able to spot some things to help you fix as well.

How sure are you that it's caused by swimming?  I suffered through shoulder pain in August and September that I thought was swim related but it turns out the real cause was my workstation setup at work.  I thought it was from swimming because I felt it a lot more after a swim but it turns out the swim was just aggravating it more.  Once I fixed things at work, the pain went away and it never bothered me after a swim.

Was about to type something similar.  Pushups, of all things, make my L shoulder very unhappy - which is then aggravated by a hard swim.  Cut out the pushups, let the shoulder cool off, back to the pool and then add pushups again s.l.o.w.l.y. and all good.  My first thought was swimming, though, so it took a couple weeks to really figure out what was the root cause.

I have no idea what your particular issue is.  Lots of possibilities (as per the many suggestions above - the best of which is to see if you can get someone to video your stroke… it's amazingly helpful, if something of bummer to see what our ACTUAL form is like, for most of us!).

I aggravated the same shoulder a bit over a year ago after a lesson in which the coach was trying to get me to, 'Swim pretty' and keep my elbows high on recovery.  Turns out that is not such a good idea biomechanically if you don't rotate much (and I wasn't).  So, after letting it cool down, I came back and now focus on rotating (as someone above said, that helps - for me it prevents impingement of the joint).

Point is, it could be LOTS of different things - from pushups to not rotating to all of the others above.  There are "usual suspects," but it's impossible to say what is your particular cause (at least for me to).  Any chance you could hand a lifeguard your phone and have them take a quick vid??  

Good luck - shoulder pain is NO fun (and neither is reconstructive surgery, speaking from experience, so I hope you fix it soon!).

Matt

Definitely look at stroke first, fix any x-overs, etc.

I will add however, that it's not all necessarily stroke mechanics. If you have a small injury from prior in your shoulder (labral tear) that could act up even with correct stroke. I have one in my shoulder that took me awhile to figure out what was making it worst - turns out it wasn't the pull power at all - it's the high elbow recovery on that side. If I lower the recovery (doesn't look as pretty), I can even use paddles no problem on that side. The best solution for me was retraining to breath to the opposite (weaker) side, which seemed to lower the arm recovery on the painful side.