i was a springboard diver for about 13 years and now i am a USA diving coach, college diving coach, TI, and AFF. my shoulders are shot. but with daily rehab i am able to keep playing pretty hard. i am only 29 but if i don't do these very simple warm ups i would very likely have more pains of my own.
another thing to think of is you do repetitive motion only one way. you need to keep both way strong.
http://www.orthoncforms.com/forms/physical_therapy/homeex/Shoulder_Theraband.pdf
i hope this helps