Sport Med Newsletter

A good read on injuries and maintenance

http://www.sportmed.mb.ca/uploads/pdfs/Injury_Newsletter.pdf

Anatomy Lesson #1- Rotator Cuff Part 2

And...back to our anatomy lecture.  In Part 1 (I was explaining the muscles of the rotator cuff (supraspinatus, infraspinatus, teres minor and subscapularis), and started to get into why they are so important to a throwing athlete.  So far we know that three of them perform external rotation of the shoulder when they shorten (a concentric contraction).  This is important, however they have a couple other functions which are even more important.

When a muscle lengthens to slow down a limb segment, that is called an ECCENTRIC contraction.  For example, when you do a ton of lunges and your butt and thighs are sore the next day, that is because the muscles are working eccentrically to control your lower body as you lunge (so that you don't just fall to the ground every time).  In the case of the rotator cuff, the muscles work concentrically to bring the ball to the throwing position, but then as you throw and release the ball they work eccentrically to control your arm as it slows down.  Otherwise, your arm would whip forward and basically go flying with the ball as it is released from your hand.

The third way the rotator cuff works for us is as a DYNAMIC STABILIZER.  This means that while our arms are doing "dynamic" things like throwing or batting, or activities like bench press and chin-ups in the gym, the rotator cuff is working to help hold our shoulder and arm away from our body.  If you didn't have a rotator cuff, then it would be pretty tough to keep your arm from flopping against your body while doing dynamic activities.  Its role as a dynamic stabilizer becomes even more important when we have previous shoulder injuries.  Because it is a "cuff", surrounding the top part of the arm and shoulder joint, it helps hold everything together.  If the muscles are strong, then we will in turn have a stronger shoulder!

So to put it all together, and relate the anatomy to our rotator cuff exercise, here is what you need to remember!  If you're not doing the exercise properly, then you're not working the rotator cuff efficiently and in some cases it could lead to injury.

1.  Make sure you keep your elbow pinned to your side.  If you are doing the rotator cuff exercise standing up, pinning a towel between your elbow and side can help make sure of this.

2.  Keep your wrist straight...don't let it bend back as you get tired or as you get close to the end of the movement.  By extending our wrist, we are working muscles that in the forearm...not the rotator cuff.

3.  Maintain an "L" shape at your elbow...don't let the weight creep in towards your shoulder as it gets heavy!  Those of you who have been corrected on this will know that it feels a lot different to do it the proper way, because it's working the rotator cuff more effectively.

4.  Once you've reached your maximum range of motion going back, SLOWLY lower the weight back to your starting position.  This works the muscle eccentrically as you control the weight back down.  Simply letting it flop next to your stomach isn't helping anything.

Keep in mind that there are lots of other ways to work your rotator cuff, so if you want some alternatives to the one we've been doing at training please let me know!

vp

Anatomy Lesson #1- Rotator Cuff Part 1

When I am supervising a training session, the side-lying rotator cuff exercise is one that often needs the most correction and fine tuning.  It seems simple enough, yet if you lose focus and don't pay attention to what your arm and shoulder are doing, you're not getting the most out of the exercise.

Here's a bit of information about what exactly the rotator cuff is, because we tend to hear about it a lot in sports that involve overhead throwing.  The "cuff" is actually a group of four muscles- 3 are on the outside of your scapula (shoulder blade) and the fourth one is on the other side, sandwiched between the underside of the scapula and the ribcage.

The muscles are called a "cuff" because their tendons wrap around and attach to the top of your humerus (upper arm bone)...this is why when you are doing any rotator cuff exercise (properly), you start to feel the burn at that one specific spot.  The rotator cuff muscles have a couple of different functions- the three on the back of your scapula (supraspinatus, infraspinatus and teres minor) are needed to externally rotate your shoulder, similar to what Kara and Korrie are demonstrating:

The muscle on the other side of the scapula (subscapularis) is needed for the opposite action- shoulder internal rotation.  When we talk about doing rotator cuff exercises we're usually not concerned with this one, because it is already very strong since it works together with pectoralis major (your big chest muscles that we work with bench press or push-ups).

When we are throwing overhand, the rotator cuff has many different roles, which is why it is so important.  First, it allows us to generate torque around our shoulder, so that we can throw with more velocity.  Check out the picture of this baseball pitcher below, his rotator cuff is contracting to allow his arm to be parallel with the ground as he gets ready to throw:

 

Your arm might not look exactly like this when you throw, but it would be pretty close depending on your technique and the flexibility in your shoulder. When we do our shoulder external rotation exercises while laying on our side, this is building strength in the rotator cuff so that we can rotate our shoulder back with more force.  The type of contraction that is occuring in this situation is called a concentric contraction, because the muscles are shortening.

As mentioned above, the rotator cuff has many different roles...stay tuned to Part 2 for the rest!  And do your exercises properly!

Manager/Athletic Therapist/Umpire/#1 Ball Shagger Val