Using BODITRAK to Improve Plyometric Landing Control
In the traditional training model, when a coach asks his athlete to jump, the athlete is expected to respond by asking “How high?” This well-known exchange reflects the expectations in sports that athletes should focus on improving their power and explosiveness in hopes to improve their performance. Without a doubt, as strength and conditioning training methods are improving, athletes in this modern era are stronger and more powerful than any other point in time. However, despite advances in surgical techniques and rehabilitation protocols, the rate of injury and re-injury for many soft tissue injuries has not improved, which may be suggest that an addition to the old paradigm of training athletes is in order.
As physical therapists, part of our return to sport progression in the clinic involves progressing from open kinetic chain and non-weight bearing exercises to close chain dynamic strengthening to jumping and plyometric and sport specific training in athletes. Just performing plyometrics to build power and explosiveness is not enough. There is a growing, strong body of literature that landing mechanics from a jump are related to future lower extremity injury risk (1 – 5). We believe that assessing and training movement quality associated with sport specific activities are paramount to keeping athletes healthy and improving performance. As a Sports Physical Therapy Resident at The Johns Hopkins Hospital Outpatient Physical Therapy Clinic, we have the privilege of incorporating the BODITRAK system when working with athletes. The BODITRAK system is an excellent adjunct to our treatment plan that helps guide our clinical decision making to help retrain fundamental movement patterns after injury to help athletes get back to the field safely and minimize future risk of injury. Specifically, we want to highlight one particularly successful example of the BODITRAK system in performing plyometrics with a competitive lacrosse player after Achilles Tendon Repair.
Achilles tendon rupture is a devastating injury and recovery from surgical repair usually results in long-term deficits in ankle ROM, ankle strength and power, altered lower extremity joint loading, and increased risk of re-rupture (6). Therefore, progression through rehabilitation requires strict time and criterion-based progression to ensure adequate healing and that the athlete is prepared for the challenges of the sport.
“There is a growing, strong body of literature that landing mechanics from a jump are related to future lower extremity injury risk. We believe that assessing and training movement quality associated with sport specific activities are paramount to keeping athletes healthy and improving performance.”
This case involves a 36 year-old male who was 8 months after Left Achilles Tendon Repair. This patient is passionate about playing competitive lacrosse, weight lifting and incorporating science into his personal training routine. His past medical history was notable for right and left knee surgeries that were greater than 10 years old. Before performing the squat jump as pictured below, he was at the appropriate timelines in healing and showed improving range of motion, strength, and was able to complete small, bilateral hopping tasks without pain or apprehension. Therefore, he was appropriate to begin larger plyometric movement such as a squat jump.
Before performing the movement, the Physical Therapist demonstrated the movement with appropriate technique and cued the patient to “land softly.” His first attempt looked like this:
Visually, his landing looks “stiff.” His landing was audible and he lost his balance backwards after landing this jump. His trunk is erect and his legs did not move and most of his weight in on his heels and shifted away from his surgical side. We could theorize that he was absorbing a high amount of force in a short amount of time. Check out what his Dynamic Vertical Force (DVF) Graph looked like:
At landing, he experienced 5.31 x BW through both legs. Again, landing mechanics, particularly “stiff” landing mechanics, are associated with increased knee loading, shear and risk of injury, but can be modified with training (7-9). Given the nature of his surgery and two previous knee surgeries, we knew that landing like this may put him at an elevated risk for future injuries when he returned to the field.
Knowing that his first attempt was not ideal, we showed him the video and graph of his steep rate of loading and how that could impact excessive load to his bones, joints and increase his risk of injury. His scientific mindset appreciated the data gathered on the BODITRAK system and seeing the force allowed him to understand how “stiff” he was landing. We further cued him to “cushion his landing like an accordion or spring.” Here’s what his second landing looked like:
Visually, he looks “smoother” with more trunk, hip and knee bending, although he is still slightly asymmetrical. Check out his DVF graph as well:
As you can see with the data in the reporting feature of BodiTrak’s ALTO app, he reached a peak of only 2.67x BW through both limbs; his DVF was cut by 50% in one trial! By teaching him to bend his knees, we were able to help him lower peak landing force by expressing force eccentrically.
Schedule a free consultation on the applications of force/balance technology in your practice.
A strength coach named Dan Cleather just posted a thread on Twitter about this subject which offered clarification on “force absorption” vs “force expression.”
“We need to accrue a certain amount of impulse to come to rest. We can either do this by landing stiffly (high force/short time) or softly (lower force/longer time).”
– Dan Cleather
By continuing to emphasize landing technique, we were able to help the athlete extend the time that he accrued force, thereby lessening the need for a high force peak and, most likely, decreasing the risk of injury.
Through his visits in the clinic we worked to ensure long term carry over. He continued to progress in plyometric quality in subsequent visits in the clinic as he would perform bilateral and unilateral landing. Check out his deep knee flexion in this jump from 3 months after the initial re-training.
By the time he was appropriate for discharge from PT, we could barely hear his feet landing on the ground. He subjectively reported improved confidence with landing and cutting as well and has progressed the point in rehabilitation to managing his agility and jump training on his own to prepare him to return to his competitive level of lacrosse. Returning to play after surgery is an uphill battle where an athlete needs to relearn not only how to generate force, but how to express force eccentrically and decrease the risk of subsequent injuries. The use of the BODITRAK provides the clinician and athlete with valuable data and feedback that can help identify and quantify a variety of components of movement. This helps to improve the clinician’s analysis of movement and allows them to collaborate with the athlete to address related deficits to progress the athlete safely to his or her highest level of function. Hopefully, tools like the BODITRAK influence the future of Sports Medicine and the model for training athlete so that when coaches ask an athlete to jump, both the coach and the athlete also ask, “How should I land?”
- Data provided a key checkpoint that would not have otherwise been a part of the rehab process. By identifying an inefficiency (and potential injury risk) in landing quality, the team at JHMI were able to attack a bottleneck in return to play.
- Data is a teaching tool. Seeing the results of his first jump “allowed him to understand how ‘stiff’ he was landing.”
- Data quantified progress which helped impart confidence. An athlete might feel like they are improving, but data lets them KNOW they are improving. Check out this excerpt from WSJ’s piece on Zach Lavine’s rehab with P3 after he tore his ACL last season:
“The only silver lining was that P3 had baseline data from before his injury. LaVine didn’t have to estimate when he felt like his old self again. All he had to do was look at the data.”
Schedule a free consultation on the applications of force/balance technology in your practice.
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