Why Do I Keep Getting Hurt?

Being able to understand how the Human Movement System works and how it can affect an individual’s performance is critical. Taking a look into the set up of the system, it has been shown that the joint support system, which is responsible for supporting the joints of the body, can be split into two different units, the local muscular system ( Stabilizers)  and global muscular systems ( Movement).

The local muscular system is comprised of stabilizers, or muscles that help keep a joint in place or limit movement.

 The global muscular system encompasses most of the major movement muscles and the muscles are more superficial.

With these two systems in mind one must have ideal functional posture, through and with the help of the systems mentioned, in order to have the least amount of stress on the kinetic chain. Dysfunction can come about through less than ideal posture, which has a systemic way of being identified.

To have ideal posture the individual would like to have a strong kinetic chain, the 3 links in that chain are

1.      Myofascial (muscular/ tissue/ length tension relationships/ reciprocal inhibition)

2.      Neural ( electrical impulses/ force couple relationships)

3.      Articular ( joint/ arthrokinematics)

A snag in a part of the chain can ultimately cause the start of the cumulative injury cycle. The worst case scenario if injury, poor posture, and/ or muscular imbalance are introduced into the human movement system is, reoccurring injury.

1. Myofascial

Let’s say that we have a volleyball player that has just suffered their first ankle sprain. It has been suggested that a lateral ankle sprain can be caused by limited range of motion in the sagittal plane (dorsiflexion)(2). Another study also found that strength in the plantar flexors also played a role in ankle sprains in volleyball players and in army recruits.(1, 3) It can be inferred that lack of strength in the dorsiflexors  or over active plantar flexors can be the issue. In this case a over active plantar flexor (i.e. gastrocnemius  and/or soleus) would be a dysfunction in the myofascial potion of the kinetic chain(1). This can also be referred to as a length tension relationship dysfunction. A muscle has a set length where it will be at its optimal functionality, and when that length is shortened, as it is in this case by an over active muscle, it can cause dysfunction. This can also lead to reciprocal inhibition, which is where the antagonist of the over active agonist will decrees the neural drive of the antagonist. This is a snag in the first of the 3 links.

2. Neural

Continuing with what could happen with this dysfunction, once the antagonist has decreased neural drive another phenomenon begins to surface, synergistic dominance. Synergistic dominance is the improper recruitment of synergistic muscles, or muscle that have the same function of that muscle, (neural chain) in this case it would be the dorsiflexors of the ankle.

3. Articular

The reason this is not ideal, is that the synergistic muscular that is know taking main stage is being over worked and can become over used and weak. This weakness of the dorsiflexors has been shown to limit range of motion in the ankle ( articular chain), which in some studies has been shown to cause ankle sprains (2).

The next post will review what one as an athlete, fitness client, or the sports trainer can do to help limit this from happening. Oh yeah I'm a Mavericks fan, hence the first image!!

References:

1. Hadzic, V., Sattler, T., Topole, E., Jarnovic, Z., Burger, H., & Dervisevic, E. (2009). Risk factors for ankle sprain in volleyball players: A preliminary analysis. Isokinetics & Exercise Science, 17(3), 155-160.
2.  M. de Noronha, K.M. Refshauge, R.D. Herbert, S.L. Kilbreath
and J. Hertel, Do voluntary strength, proprioception, range of
motion, or postural sway predict occurrence of lateral ankle
sprain? British Journal of Sports Medicine 40 (2006), 824–828.

3. R. Pope, R. Herbert and J. Kirwan, Effects of ankle dorsiflexion
range and pre-exercise calf muscle stretching on injury
risk in Army recruits, Australian Journal of Physiotherapy 44
(1998), 165–172.