Last week, we began to discuss the concept of rapid neuromuscular response or RNMR. This is a form of training where we train the athlete to have a rapid response to an external stimulus which results in whole kinetic chain stability. We typically use perturbation training with this and in our last blog we discussed some simple concepts to keep in mind with perturbation training. With this type of training, we start with some simplistic movements and go to more complex ballistic types of movements. As an example, I will go through a series of single leg exercises from simple to much more complex. The goal of this series is that the athlete is training for stability in single limb performance. When I say that, I want them to control both the magnitude of frontal plane motion and speed at which that motion occurs.
Last week, we also talked briefly on perturbations and what those are. We also stressed the importance of making sure we are training the types of movement patterns we want (stability). Considering, our stress should not exceed the athlete's ability to provide stability to the stimulus. However, before we move on, we must also discuss the concept of both anticipated and unanticipated perturbations. As far as a progression goes, I will start with anticipated (where the athlete knows this stimulus is coming) to more difficult unanticipated (where athlete does not know what rep the perturbation may occur on). This series we will discuss just an example of a progression keeping in mind there are a lot of ways in which we can alter this and change it up.
We will go through a series of single leg exercises. Before we do, I would like to highlight some of the things we see when we look at our movement data.
Hip position - athletes have a very hard time maintaining proper hip position during the course of single leg exercises. As mentioned in the beginning of this blog series, there are some common hip patterns we see where the athlete loses control of the pelvis during single leg tasks. Keeping that in mind, if we do not correct this during single leg training, then this will be a pattern they continue and will carry this over in sports.
Control frontal plane motion - we have talked a lot about this but this is especially critical in our training. Our goal is to aid them in controlling the speed at which this motion occurs. Are they still going to fall into a dynamic valgus position? Most likely yes. But, when they do, we want them to control the speed at which they fall into that position. Therefore, as a part of our training, we must work on them controlling this motion. If they loose the ability to control this motion, simply step back the exercise. What I mean by this, is if they are doing a single leg squat (where the contralateral limb is off the ground) and unable to control the frontal plane motion, then step them back to a split squat where the contralateral limb is in contact with the ground. This is a more stable position (easier) and they can still work on the neuromuscular control to control this position. This is better than simply stopping the exercise as is or continuing it. Continuing the exercises reinforces the negative movement patterns and stopping does not help build the level of endurance they need to control.
Considering the above, the following is a sequence we will use for RNMR.
Single Leg Lunge RNMR Series. This is an exercise we all use a lot and are familiar with. However, in this example
we will start with the athlete performing a set number of reps and then provide perturbation at a given range. (20 - 45 - 90 degrees knee flexion).
Once technique is mastered, this is progressed to performing the single leg lunge with the spiral technique. The spiral technique uses the theraband CLX band wrapped around the stance leg in a very specific manner. For specifics on this technique, please refer to the following video. The end of the clx is held by the clinician and can be used to provide perturbations (pulling the band in a medial and diagonal fashion - resulting in an adduction and internal rotation force). This would start with performing this through concentric phases then concentric and eccentric phases.
Once technique is mastered, then this is progressed to include (without the band) upper and lower body perturbations. From there we move to performing with split squats, to single leg hops. Once technique is mastered, then this would progress from anticipated (knowing this will happen on every rep) to unanticipated.
Obviously there are 1000s of variations that can be performed with this sequence. You can add doing landing to take off in sprinting. Or running to do a jump with indirect contact, to change in direction (much later phases of rehab). Key is to make sure we are training the movement pattern we want (control of frontal plane motion of the knee and transverse, sagittal and frontal plane motion of the pelvis).
This is just one example but should give you an idea of how we are using perturbation training to aid in creating these rapid neuromuscular responses to control movement. Next week, we will take a dive into how deficits in quadriceps strength can add to kinesiophobia and changes in frontal plane biomechanics. Stay tuned as I am super excited to share with you. Have you followed my instragram @bjjpt_acl_guy lately? If not, you are missing out. I am constantly posting the latest research in injury prevention and sports medicine. Don't miss out and 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