Those "Tricky" Hamstrings (Part 1)

Ever noticed how often a hamstring injury tends to "recur" or never fully recover?  In the 2016 season, MLB saw it's highest rate of hamstring injuries since at least 1998.  A total of 53 applications of the MLB Disabled List were due to hamstring injuries last year, a rise from the average 34.5 occurrences in past years.  This does not include those injuries that did not require a trip to the DL.  Why the rise?  Why do they seem to recur?  I remember reading a quotes from a former MLB head trainer, simply stating that "hamstring injuries are tricky".  In some cases this may be true, however, I believe there is more to the story.

A recent study found that pelvis stability may have a larger influence on hamstring injuries (particularly sudden injury) than a strong hamstring contraction in any single stride. Furthermore, the lumbo-pelvic region has been found to have more influence on hamstring tendon tension than muscles of the knee and ankle. Journal of Biomechanics article  Makes you wonder if maybe traditional philosophies on hamstring injuries are missing a major concept...or two. 

I believe we need to re-think our preventative and treatment protocols and look at the human system as a whole in order to decrease injury occurrence.  I truly feel that the rise in such injuries is a result of the big push to prevent "tight hamstrings" at all costs. Typical programs include stretching the hamstrings... without real regard to why and if this is even necessary.  In addition, I feel that most preventative and treatment programs tend to minimize the role of the nervous system, including the integrated interconnection of the body as a whole. There also seems to be little understanding of the role of muscle POSITION and the rotational components of our hamstrings during rehab and strengthening activities.  Typical hamstring strengthening programs tend to focus on one-dimensional strengthening vs tri-planar strengthening and are often performed on muscles that are set-up to be inefficient. 

TO STRETCH OR NOT TO STRETCH?

Let's break down the first concept.  Perhaps hamstrings that feel "tight" do not necessarily need to be stretched.  Our muscles have attachment sites that influence their resting position.  A muscle that is being pulled at one attachment site will rest in a longer-than-ideal starting position.  Each of our muscles has an ideal length that it functions most optimally in.  A muscle that is longer or shorter than that optimal position is going to function, well, sub-optimally, regardless of how much weight it can push around.  Get this... the majority of athletes I see with hamstring injuries actually present with hamstrings that are POSITIONALLY inefficient, long, inhibited.  In this case, stretching will only place the hamstrings in a more vulnerable position and the injury will likely return.  

Let me explain.  We (especially athletes) function predominantly in a "state of extension".  Visual focus, habitual movements, "hopped up" autonomic nervous systems, prolonged sitting, minimal rest or sleep, and rigorous travel schedules (to name a few) all contribute to this nearly chronic state of extension.  One result of this extended state is a pelvis that tips forward of ideal or "neutral" position.  This can happen on one or both sides of the body. The hamstrings have an attachment site at the pelvis.  When the pelvis rotates forward, that attachment site rises.  The result is a hamstring group that is now longer than it should be at it's resting state.  A longer-than-ideal muscle is a weakened, inefficient and (most importantly) under-stimulated muscle. 

SO, WHY, THEN, DO MY HAMSTRINGS FEEL SO TIGHT?

You know the drill.  Stand up and try to touch your toes.  Or, lay on your back and see how far you can bring your foot toward your face.  Or, my ultimate favorite... "sit and reach".  But, what exactly are you testing?  Countless times I've been told by patients and clients that "I've never been able to touch my toes" or "My hamstrings have always been tight, no matter how much I stretch".   I have no doubt that they FEEL tight or that the ability to bring their leg up toward 90 degrees is limited.  This does not, however, indicate the actual muscle tissue is short or "tight". 

Let's look at this from a commonly-assessed position, supine.  When the pelvis is tipped forward and the upper attachment site of the hamstrings is elevated, getting a hip to bend to 90 degrees requires more length out of the hamstring than a hamstring that is starting in a correct position.   If a hamstring group that is attached to a forward pelvis is not (yet) over-lengthened, it SHOULD prevent that hip from bending up to 90 degrees... the further forward your pelvis rotates, the further from 90 degrees you SHOULD BE.

What I am saying is that it is okay if you can't get your leg up as high as others.  That is not your problem.  The problem is that your pelvis is forward... and that is how hamstring "tightness" should be addressed.   I am also saying that, if you can get your leg up to 90 degrees or more, you better hope your pelvis is "neutral".  Otherwise, you have over-lengthened you hamstring group. 

TO SUM IT UP

Tight muscles do not necessarily need to be stretched. 

Hamstring function is highly dependent on the position of the pelvis. 

Most hamstrings are positioned in a lengthened, inefficient position.

Stay tuned for my next post, where I will discuss the role of the Nervous System on hamstring injuries.