A few weeks ago I was able to attend the Rehab and Injury Prevention seminar by Bosch, Pryor and Egger. It was held on the campus of University of North Carolina.
I first came across Frans Bosch with his book Running a few years ago and his book Strength Training and Coordination most recently. Both books are excellent and should be read. With that being said, the Training and Coordination book, If you are like me, needed several rereading of chapters. I'm happy to say, that after the seminar many of the concepts became much clearer.
I'd thought I'd share a few concepts and notes that I'd written down and my overall take aways.
Mortal control is having enough stability.
One of the best explanations of Dynamic Systems theory is the self organization of high variability (start) with (middle) synergies (cooperation between a number of components that correct each others errors) to a stable end point (finish).
This then becomes a map of how to define training and rehab. (my personal interpretation)
For example: Self organization at the intramuscular level. Fiber variability (using more) to fiber synergies, to a stable contraction.
Self organization at the intermuscular level. Force variability to force synergies to stable contraction.
Analyze the mid stance in gait as it's the most stable. Not push off.
Fundamental: Experts have the most variability to reach the most precise endpoints. The less variability you have to get to an endpoint, the more likely you get injured.
Slow twitch muscles have actually bigger elastic component.
One of the more interesting topics to me was the concept of muscle deformation and muscle gearing. This is a topic I've tried to read on and didn't come up with much. Now, knowing the main researcher was Roberts and how shape of the aponeurosis changes with pennation has lead me to really cool articles like this one. Muscle Fiber angle, segment bulging and architectural gear ration in segmental muscle.
I think the aponeurosis being able to expand on contraction freely is potentially one way manual therapy has an influence on muscle health.
Muscle gearing is a way for force sharing and helps to not allow shear to come into play. Shear creates muscle injuries. (deep dorsiflexion produces shear) So training is designed to eliminate that position. Resist it!
On contraction there is lateral expansion, (think trying to compress water) lateral push forces, the aponeurosis gets tight and we get stability. The aponeurosis bulks out. Best way is isometrics.
Zooming out of this micro to macro is joint coupling. Biotensegrity, the push and pull of forces combined build into bigger units.
Ankle stiffness is super important. Can't be world class if there is dorsiflexion.
Running on grass will teach you to use the tendons better. (running over slightly different surfaces is one type of variability that is taught to teach better running)
Free hip needs to be higher in running. (this will be a foundational drill)
Concepts of Co-contraction are big. This is multiple muscles contracting to produce coordination as well as reducing degrees of freedom.
3 P's to Train Co-contractions.
1. Pretension: Reduces slack to co-contracting
2. Perturbations: Solve context related variability by co-contracting
3. Pressure (time) Solves slow feedback loops by co-contraction
Create the environment for both coordination and conditioning. For example: Run 20 meters with the weight plate out in front of you, looking through the hold. At 20, stick it out to your side, keep running forward and keep looking at it through the hole.
Don't coach the process, coach the outcome. (big deal) Allow the athlete to figure it out.
Co-contraction is a skill that must be trained.
Wear marks on shoes are irrelevant. As first contact has no substantial ground reaction forces, no change in muscle activation. Early heel off is where the important stuff lies.
Running injuries at toe off is most important. Looking how to stability can change. Hamstring is a huge storage vest for elastic energy. Lack of pelvic control = hamstring injuries.
Imbalances in muscle activity lead to shear. (my take, this is potentially another place where manual therapy plays a role)
Swing leg retraction as quick as we can. Think of closing the scissors. Very important. Running is done in the air, not on the ground. You want the swing leg knee to be in front of the stance leg on foot strike.
Key to sprinting is putting the horizontal component into the sprint. Christoph Lemaitre was given as an example as he has sprinted very fast times and is remarkable weak. (I wonder if he knows he's being bashed ...ha ha)
80% of glute max is inserted onto the IT band. Glute is a stabilizer. IT band stores and recoils energy.
Soleus to the Achilles as is glute to the IT band. Muscles to the tendon.
If your locked into anterior tilt of the pelvis you can't get frontal plane movement. (PRI and more importantly Pat Davidson does an amazing job of getting stability into frontal plane)
This is important for therapists whose patients ask why are they hurt or in pain.
Why do we need variability? Because we need to cope with an environment of variability. Why do we get imbalance? We have removed the variability in our environments.
Also why I think distance runners need to run trails. (soapbox)
Injury changes motor control. You get receding peripheral control. First, when you are injured you get receding co-contractions. 1. Intention is the crude signal. 2. Coordination at the spinal level.
Receding proprioception is the 2nd thing when injured.
Examples of dumb training. Jumping with resistance bands as resistance as your body doesn't need to produce the co-contractions, it can just lean on the antagonists.
Injuries lead to reduced variability.
Joint angle velocity is an important concept. It allows us to remember movement patterns and is body independent. For example, learning to snowboard as a kid, it will come back years later even though the body shape has changed. Movement patterns that can used everywhere, the body wants to store them.
Teaching the Intrinsic training.
1. Unexpected Perturbations. (Use of water sloshing logs on certain exercises)
2. Environmental cues.
3. Using time pressure.
4. Using differential learning. (batting on a mattress, ruby hooker throwing in on different surfaces
5. Using endpoint focus. Finish with your foot here on the wall
6. Using double tasks. Combining different methods
Don't allow counter movement in training. The body gets used to slack. This means like jump from a static position. (crazy how bad I was at this at first)
Elasticity only works under isometric conditions.
Examples of Poor Hamstring function in running. (why high speed sprinting isn't enough to improve hamstrings)
1. poor ant-post pelvic control leading to poor proximal loading
2. lower leg doesn't travel out far enough to apply stretch
3. leads to lazy hamstring and loading of other muscles, such as gastroc, glute and adductors.
Hamstrings must be trained with 1. speed 2. strength (isometrics ) 3. Robustness (perturbations)
Body is interested in forces. Perhaps rehab has it all wrong? Don't start with the little bands to rehab a shoulder but a heavy load that it can resist with high force. The minimum Jerk Principle (To find the place where the body has the least jerk, but the most challenge w the Jerk.
You don't learn from movement, you learn from the sensory information you get from that movement.
High EMG reading with low force = Insufficient. Low EMG reading with high force = Money! An example of what we don't want is the barbell hip thrust. High EMG, low force.
Why Tennis players rarely blow their ACL. The hitting of the ball requires trunk lean, this protects the knee, also the hind leg catches up quickly. Take away is teaching the trunk to land over the plant leg...IE volleyball landing as well.
Differential learning basically means mix it up.
For myself, I learned more about muscle gearing and where to keep looking, I want to learn more about Riemannian geometry and further figure out what that means for therapy and training. It really cleared up some concepts with the 3 P's in training. I do enjoy learning from different pools of thinking and the more I learn the more I can see some crossover and linking of people. Pat Davidson with his PRI background does awesome work with his frontal plane training. Functional Range Release and Spina and Chivers lectures were and still are, ahead of the curve with some of the science. I got to hang out with an old friend Jonas, who I first met back in the bobsled days, who is now the UNC mens basketball strength coach.
This was an outstanding seminar. The lectures either hit on topics I wanted to learn more about or stimulated new thoughts. The practical was unbelievable. John Pryor and Leigh Egger did a remarkable job of taking the science and making it practical. There were several concept drills I thought I knew and didn't ( I was teaching them wrong, sorry athletes) There were some that even after reading and understanding, needed a different way of being taught for me to get the Ah ha moment. Time pressure was big for me, feeling it.
Hopefully if you had an interest, after reading through my notes and ramblings you will be convinced to check it out.