This article is from the Fitness FAQ, by Jeff Gleixner (glex@cray.com) with numerous contributions by others.
also check FAQ #29
Short explanation of various exercises to strengthen the shoulder and
Rotator Cuff:
SHOULDER ABDUCTION: Stand with elbow straight and hand rotated
outward as far as possible, raise involved arm to the side of
body as high as possible, Hold for 2 seconds, then lower.
SUPRASPINATURS-"Empty Can": Stand with elbow straight and hand
rotated inward as far as possible, raise arm to eye level at
30-degree angle to body. Hold for 2 seconds, then lower.
PRONE HORIZONTAL ABDUCTION: Lie on table on stomach with involved
arm hanging straight to the floor. With had rotated outward as
far as possible, raise arm out to the side, parallel to the floor.
Hold for 2 seconds, then lower.
SHOULDER EXTENSION: Lie on table on stomach with involved arm
hanging straight to the floor. With hand rotated outward as far
as possible, raise arm straight back into extension as far as
possible. Hold for 2 seconds, then lower.
90/90 EXTERNAL ROTATION: Lie on table on stomach with shoulder
abducted at 90-degrees and arm supported on table with elbow bent
at 90-degrees. Keeping shoulder and elbow fixed, raise arm into
external rotation. Hold for 2 seconds, then lower.
SIDE-LYING EXTERNAL Rotation: Lie on uninvolved side, with involved
arm at side of body and elbow bent at 90-degree angle. Keeping
elbow of involved arm fixed to side, raise arm into external
rotation. Hold for 2 seconds, then lower. -- The therapist I saw
suggest folding and rolling up a towel into a short cylindrical shape
about 4"-6" in diameter 8"-12" long and placing it between your elbow
and your ribs of the involved side.
SITTING DIP: Sit on edge of chair. Gripping sides of chair with
hands, straighten arms, lifting buttocks off chair seat. Hold
isometric contraction for 5 seconds then lower. -- Can be done
using a dip bar. Keep body straight and only go down 3"-4". Try
to use the shoulders to do the whole movement.
Additional Rotator Cuff exercises:
Using rubber tubing or Thera-Bands attach one end to a pole,
door knob, etc. about waist to chest high. A low pulley
machine can also be used, sit or kneel if using a pulley.
Same position as Side-Lying External Rotation except that you're
standing with the secured end, or pulley, to the uninvolved side of
the body. Involved arm is at 90-degrees in front of body (broken arm
position), the handle or tubing held securely in your hand. Keeping
the elbow against ribs, or towel as suggested above, pull and rotate
outward about 135-degrees from chest. Upper body is motionless all
that's moving is your forearm. Hold for 2 seconds, then return to
starting position.
Same as above only the attached end is to the involved side of the
body and it's a pulling and rotating toward the chest.
To help the throwing muscles:
Again using rubber tubing or Thera-Bands attached about chest
high to something.
Facing away from the attached end with arm in a throwing position
(90-degree angle between upper arm and ribs and 90-degree angle
at elbow, forearm at a slight angle backwards.) Hand facing
forward and holding the rubber tubing. Rotate forearm forward
about 30-degrees, hold for 2 seconds, then return to starting
position. The hand only goes through a 6"-12" arc. The only
thing moving should be your forearms.
Same as above except you face the attached end and you pull
back to the starting position of the above exercise.
 
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