Running posture and injury
Clinical Observations
A longer post today that may ask
more questions than it answers! Hopefully it will be engaging and encourage the
interested reader to explore the practical applications from our discussion.
Running is a skill that must be
learned, to perform efficiently. Although we are not taught to run from an early age, the fundamentals are probably hard
wired into the brain from about 18 months, when toddlers decide to move around
faster. As with many movements they are refined in the early years of
development and certain habits and postures are picked up and retained for a
variety of reasons.
The human nervous system learns
required motor patterns and uses those in the most efficient way possible (this
is not to say it is the most efficient
way), it’s almost the path of least resistance. In fact it may be down right
dysfunctional! For this reason, it is hard to unlearn a motor pattern. In fact,
experts who study pain involvement and the nervous system would tell us that
you cannot ‘unlearn’ a motor pattern, but you can learn a new motor pattern in
preference to an old one. For this very reason ‘poor patterns die hard!’
While the fundamentals of running
biomechanics are there for most, if and when we decide to start running as a means
of exercise we often carry these patterns over. With continual training we then
drive them home as we constantly pound the pavement in an effort to get fitter
and faster. Dysfunctional patterns are re enforced with every step.
Before we look at the running
posture it’s important to understand we are talking about distance running and
not sprint running – the two have vastly different running mechanics.
The major influences;
Posterior pelvic tilt
A posterior pelvic tilt is a common
problem. It becomes more pronounced and noticeable as we become sedentary and
seated in our day jobs. Poor pelvic position seated may carry over to our
athletic and running endeavours.
While there are differences in
pelvic angle regarding ethnicity ie; Afro-americans have a more anterior pelvic
tilt and Asian countries tend to be slightly more posterior, most of us tend to
fall into this position. We then adopt this new position rather than retaining
our anterior to neutral pelvic angle developed during our growth and
developmental years.
A posterior pelvic tilt tends to
reduce boney and myofascial stability around the lumbar spine causing load
through the intervertebral disks. This position also ‘locks’ the SIJ,
encouraging a hitch through the swing phase during gait. Further to this, lack
of extension in the hip is observed. Lack of extension through the toe off
inhibits full activation of hamstrings and glutes. The trade off being
facilitated quads and hip flexors further compounding the problem. This often
reduces firing of the gluteus medius especially the posterior portion being
placed on such length in the eccentric position during midstance.
The last big notable problem arising from posterior rotation of the pelvis is over striding. Over striding places increased loading on the anterior structures as they eccentrically load through increased ground contact time. This increased contact time forces the calves to work over a longer period of time, often these are the runners that complain of ongoing calf injuries. This is also a culprit in rear foot loading and ground collision - an area of hot debate at the moment with the popularity of bare foot running (a topic in itself)
Kyphotic thoracic spine
A kyphotic or ‘rounded shoulder’
position may be adopted over time or may be due to a particular disease process
(osteoporosis, scheumanns disease) or a predisposition. We will focus on the
adopted form.
Lack of extension tends to occur as
we leave our developmental years and assume more sedentary postures. It does
not occur over night. With rounded shoulders, flexion through the mid to upper
thoracic spine occurs ‘opening up’ our facet joints and causing us to become
stiff and less mobile.
With flexion in the thoracic spine
comes a loss of rotation. Rotation in the thoracic spine is extremely important
in the counter movement of the opposite hip/SIJ. As the left hip drives forward
from mid to terminal swing phase, the right shoulder and thoracic also rotate
to the left, causing a counter rotation. This also assists in preparing the
myofascial system to ‘wind up’ and store energy through the right latissimus
dorsi and left glute max. Activation of these structures causes closure of the
SIJ giving stability to the pelvis. A lack of mobility can therefore cause
instability to the SIJ setting up a myriad of problems
Anterior displacement of the pelvis
An anterior displacement of the
pelvis typically occurs in those hyper mobile persons or those standing for
long periods of time. If this position is adopted during running posture a
variety of problems can occur.
If coupled with an anteriorly
rotated pelvis there will be impingement in the lumbar spine loading the disks
at L4/5 and possibly referring posteriorly down the thighs. Conversely when
coupled with a posterior rotation (more common) the hip flexors become so
overactive eccentrically trying to control the forward position of the pelvis,
the glutes go into hibernation. This causes similar problems to a posterior
rotation alone though to a higher degree.
Pelvic stability is often a key
factor for this type of runner (posturally speaking) - usually there is joint laxity about the
hip/SIJ and stiffening up of the joint(s) and placing them in a better position
often improves dysfunction about this area.
With poor joint stability, increased
loading and forces will be taken up by boney and joint surfaces as opposed to
connective tissue, which are better designed to withstand compressive and
tensile loads. Soft tissues also repair to some degree where as joint surfaces
do not!
Anterior pelvic rotation
This scenario is a problem far less
frequently from a clinical perspective unless it is a big rotation. This tends
to load up the lower lumbar spine causing stiffness and possible impingement.
This is also the runner that tends to land in a more pronounced forefoot
position, giving the calves and achilles a lot to think about!
The bigger concern is a compensatory
kyphosis of the thoracic spine (discussed earlier).
Unilateral rotations of the ilia (including inflare and outflare)
These do present in the clinic and
can be either from long term occupational overuse or from an acute episode ie;
lifting. Usually they are easy to assess and gain control over. The side that
rotates away from the ‘normal’ for that person will usually be the symptomatic
side.
BUT, if the rotation is not attended
to early, compensatory patterns can set in making the treatment process a
little more complicated.
Final Thoughts
It always amazes me that most sports
even at a club level will consider form and biomechanics as an important of the
development of an athlete yet running is an assumed skill. Running is a skill and similar to all skills it must be developed.
Runners at national level do not practice form - it is a case of physiology and
‘just going harder’ unfortunately, this does not always work.
The question might be, are these
runners at this level because they are more economical and efficient and
adopted good patterns early on, or did they develop this as a way to get faster, fitter etc?
Treatment for the running athlete
will be addressed in a future post. Until then…..
Happy Running!
Jimmy
I am happy to discuss further if
anyone would like to contact me
Jimmybarker9@gmail.com
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