Monday, December 16, 2019

The Evolving Knowledge of Movement - Part V - What We Know Now

Assessing movement and getting objective data is important.  But that is not as nearly important as getting actionable data.  Actionable data is data that relates to injury risk and which we can actually do something about.  Actionable data is what we are talking about throughout this series.  Last week, we discussed speed of motion and some exercises we could do to improve that.  This week, we will talk about direction of movement.

Direction of movement impacts speed!

One of the tests that we perform is called a hop plant (in the video here).  During this test, the athlete hops in four directions (forward, backwards, lateral and medial).  During the course of the test, they are instructed to keep the contralateral leg off the ground so stability has to solely come from the limb being tested.  Since tracking this on over 14,000 athletes, one trend we have seen is that there are much higher numbers (magnitude of valgus and speed of valgus) associated with the medial hop.  If you dissect this motion and what is going on, it makes a lot of sense.

In this motion the athlete is standing on one leg.  They must push off on the lateral aspect of their foot with enough explosive power to get their center of mass moving medially.  At landing, they must resist the medial momentum at the knee and stabilize the knee and prevent from going into a valgus position.  At the same time, they must also activate the core and hip to counteract the medial momentum of the center of mass (trunk) from continuing to move medially.  This is obviously a very challenging motion but also one that is very relevant to sports.

What we know is that athletes who's motion exceeds 20 degrees of valgus at speeds higher than 220 degrees/sec tend to have more chronic lower kinetic chain issues (meaning non-contact ankle injuries, hamstring strains, etc).  We also know that if we can improve these numbers, the frequency of these non-contact chronic chain issues goes down. 

Aside from some of the exercises that we talked about last week, simple training in multidirectional plyometrics is vital.  I say that and I'll bet the majority of folks reading this are like, duh.  But here is the thing.  Simply training those ALONE will not do it.  It must have a combination of the types of exercises that we mentioned last week in addition to "proper" multidirectional plyometrics.  What I mean about that, is that it is not simply about the ability of the athlete to perform the task.  It is about the ability of the athlete to perform the task while  maintaining frontal plane stability at the knee and stability at the hip.

As an example, if you look at the athlete here.  She is performing the task and successfully, but she has a lot of internal rotation, some valgus and her hip is dropping on the left side indicating right sided gluteus medius weakness.  If I were to train this athlete and let her continue to do these plyometrics in this fashion, she would get stronger.  But the default movement pattern that she would rely on would be this movement pattern.  Hence I am training her to a potential injury down the line.  If she is unable to perform this task without allowing her knee to go into valgus and her hip dropping, then I need to step this back to a less aggressive exercise until she is strong enough to do this with proper movement.

In other words, we should focus less on the ability to perform the task as the pre-requisite of progressing someone's program and focus more on the fact can they do it with proper movement.  As basic as that sounds, this is where we fail all too often.   We hope you have found this useful and is something you can take away and implement tomorrow with your training or with the training of your athletes. 

Next week, we will continue that discussion on the impact of concussion on lower kinetic chain movement.  Stay tuned as I am super excited to share with you.  If you enjoy this blog, please share with your colleagues, athletes and training partners and please be sure to follow us on instagrm @ bjjpt_acl_guy and twitter @acl_prevention.  Train hard and stay well.  #ViPerformAMI #ACLPlayItSafe

Dr. Nessler is a practicing physical therapist with over 20 years sports medicine clinical experience and a nationally recognized expert in the area of athletic movement assessment and ACL injury prevention.  He is the founder | developer of the ViPerform AMI,  ViPerform AMI RTPlay, the ACL Play It Safe Program, Run Safe Program and author of a college textbook on this subject.  Trent has performed >5000 athletic movement assessments in the US and abroad.  He serves as the National Director of Sports Medicine Innovation for Select Medical, is Vice Chairman of Medical Services for USA Obstacle Racing and movement consultant for numerous colleges and professional teams.  Trent has also been training in Brazilian Jiu Jitsu for 5 years and complete BJJ junkie. 

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