Archive for the ‘Physiology’ category

Bridges – How to spare the back…

March 5, 2010

A couple of weeks ago, a reader asked me to drop some comments on bridges.  It was asked something along the lines of why do coaches insist that gymnasts straighten their legs and keep their feet together when bridging?

I don’t know.

As I noted in my last post, repeated bouts of lumbar flexion are believed to be a potential risk factor lumbar spine disorders such as a herniated disk.  Just the same, the lumbar spine really is not made to excessively arch or hyperextend as is seen when gymnasts perform skills such as bridges, backbends, and back walkovers.  Aside from these skills, when does a gymnast actually assume this type of a position?

Quite honestly, I cannot think of any other skills in which a gymnast assumes this position with so much lumbar hyperextension.  Some may argue that this type of bridge development is necessary for a successful performance of a back handspring.  Or, that’s an argument that I’ve heard a few times over the years.  Is it really?  Below, are three screenshots taken from Shawn Johnson’s first tumbling pass at 2008 National Championships.  Notice that she never gets into the position that we see above and if she did, she wouldn’t be very successful.

Beginning of the BHS After the RO

Flight Phase of BHS - Just Before Hand Contact

During Hand Contact of BHS

Does any gymnast ever assume the position (as shown in the bridge picture above) in a back handspring or any other skill except for bridges, back/front walkovers, etc. ?  The important factor in bridge development is shoulder flexion or often – hyper-flexion.  In other words, we want the arms to be able to be lifted up by the ears or even past without the chest/ribs poking out.

As I discussed in an earlier blog posting, there are other factors that we must consider when a gymnast has “tight shoulders.”  Maybe the issue is not flexibility at all.  Maybe the issue is too much rounding of the upper back that which places the scapula in a poor position.  Maybe it’s a matter of poor scapular stabilization or an imbalance of the scapula musculature.  The key muscles that would limit shoulder hyperflexion are the latissimus dorsi and the pec major/minor.  There are other stretches specific to these muscles that do not stress the low back.

With that said, here is a better way to perform a bridge.  I first came across this suggestion from David Adlard in an old USAIGC publication called STEPing UP.  To minimize the excessive hyperextension of the low back, elevate the feet to above shoulder height and put the emphasis of the stretch on the shoulders.

In the picture below, a trainer colleague, Becky (who used to cheer and tumble in high school) demonstrates.  Thanks Becky!  She’s a little tight in the shoulders, but now this position can better emphasize the muscles that need to be stretched without putting the low back at as much risk.  Afterwards, she even commented something to the effect of – “Wow, that really stretched my upper back…it felt good…”

Feet Elevated Bridge

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Do we really need to be doing sit-ups & crunches?

March 4, 2010

Dr. Stu McGill from the University of Waterloo in Canada has strongly advocated that repeated lumbar spinal flexion (i.e. rounding of the low back) may ultimately lead to a disk injury.  The question that remains unanswered is how many will it take to lead to injury?  That’s probably a question that is HIGHLY variable depending upon the individual.

Nevertheless, I have pretty much stopped doing crunch/sit-up-type exercises.  I feel that you can achieve the same effect performing core stabilization exercises such as planks.  The closest that I come to a crunch is a reverse crunch, which I feel is a lead-up to performing a candlestick/lever raise on the floor, hanging on a bar, on the rings, etc.

With that said, here’s a study that was conducted on US Army recruits comparing a sit-up training program vs. a core stabilization program on performance of the US Army Physical Fitness Test.  What was found was that –

“….there was a small but significantly greater increase in sit-up pass rate in the CSEP (5.6%) versus the TEP group (3.9%).”

CSEP = core stabilization exercise program

TEP = traditional exercise program

Effects of Sit-Up Training Versus Core Stabilization Exercises On Sit-Up Performance

Medicine & Science In Sport & Exercise. 41(11):  2072-83, Nov 2009.

What are your thoughts?

Proper Landing Mechanics

February 6, 2010

Received an e-mail the other day requesting more information about proper landing mechanics. Here’s an excerpt from the e-mail:

Could you talk a little about landing positions, if you haven’t already done so?  I remember reading a comment recently about coaches emphasizing legs together on landings, but it makes more kinesiological sense to have knees and feet shoulder width apart.  The Gymnastic Minute on YouTube addressed the correct landing posture today, but I’d like to have a more in-depth explanation.

Here’s the YouTube video that this individual is referring to:

In terms of the feet being together versus apart, a wider base of support allows for more stability.  Secondly, it is nearly impossible to get the hips shifted back enough to allow the glutes and hamstrings to assist in absorbing the energy from the landing if the feet are together.  Why is this important?

Well, here is an article from the NSCA Performance Training Journal (a free online publication on the NSCA’s website) that explains matters more in-depth.  However, I will give you a brief overview.

The hamstrings originate on the ischium of the pelvis and attach on the back of the tibia (shin bone).  Their main job is to bend the knee and their secondary job is to open or extend the hip.  Well, as the knee bends from a landing, the hamstrings will activate and pull the shin bone backwards.  This takes some of the stress off of the anterior cruciate ligament (ACL).  The ACL attaches at the back of the femur (upper leg bone) and the front of the tibia.  Its main job is to prevent the tibia from moving forward too much.  So, if the hamstrings activate and pull the shin backwards, this takes some of the load off of the ACL.

Now for the glute max.  The glute max’s main job is to open the hip (extension).  However, the glute max also helps in controlling rotation of the femur since it partly inserts on the greater trochanter of the femur.  (I say “partly” because part of it also forms with the TFL and creates a sheath that runs down the side of the leg known as the IT Band and this connects on the side of the tibia)  Further, it assists the gluteus medius (as Kris Robinson mentions in the YouTube clip) in preventing the knees from dropping in – known as “valgus” position.

Controlling rotation of the femur and preventing it from dropping inward is very important to knee health.  Coupled with an inwardly rotated tibia,  you’ve got the makings for disaster.  This is why what appears to be a perfect landing could end with the gymnast on the ground in agonizing pain.  Having been witness to a couple of these in my coaching career, I now have a better understanding behind the “why.”

While this is all well and good, the problem is that gymnastics promotes a quad-dominant landing despite the obvious biomechanical problems that it presents.  Despite the traditional gymnastics approach, I encourage all of you to think about the health of your gymnast and consider having them bend at their hips a bit more and push their butt backwards to allow for the glutes and hamstrings to engage more and assist in absorbing the landing.  Your gymnast’s knees will be thankful later.

Anyway, I hope this offers some insight into proper landing mechanics and their importance.

Sports Rehab to Sports Performance Teleseminar 2010!!!

January 26, 2010

For those of you who are really geeky like me, here is a link to a series of FREE teleseminars on a variety of topics related to sports performance, rehab, injuries, etc. etc.  And, the best news of all – It’s FREE!!!!

CLICK HERE for the website where you can sign up.

One interview per week, for eight weeks, starting Wednesday, January 27th. Each interview will last from 45 to 70 minutes (depending on the speaker). 8:00pm EST each Tuesday night through March 24th. If you can’t make the call, don’t worry! It will be made available for another 24 hours


Speakers include renowned physical therapists, chiropractors, strength coaches, & athletic trainers.

If you know anything about the physical therapy/rehab world, names like Craig Liebenson, D.C.; Shirley Sahrmann, Ph.D, PT; Stu McGill, Ph.D; Michael Reinold, PT, DPT; etc. are some of the most respected names both nationally and internationally and folks that will be participating in this teleseminar.

If you have any questions about who any of these folks are and what they have done, please leave your question in the comments section and I’ll respond accordingly.  With that said, if you type their names into the PubMed research database, you should find quite a few peer-reviewed journal articles by each listed.

The interviews will be made available for up to 24 hours afterwards.