Latest / The Gill Athletics Track and Field Connections Podcast / #44: Gill1918 presents Evan Nelson "the Cause of Running Related Inuries"

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#44: Gill1918 presents Evan Nelson "the Cause of Running Related Inuries" · The Gill Athletics Track and Field Connections Podcast

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  Welcome to the Gill 1918 Project, a podcast series by
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  coaches, for coaches, powered by Gill Athletics.
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  Think of this as the Ted Talks of track and field coaching.
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  Short, insightful, and packed with valuable strategies to help
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  you grow as a coach. We're bringing the once a year
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  track clinic straight to your ears daily.
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  Interested in creating your own episode?
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  Everyone's welcome to participate.
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  Check out the show notes below For more information.
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  Now let's get into today's topic.
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  This is Alvin Nelson, Director of the Velocity Project and
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  associate Professor at the University of Wisconsin.
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  Today we're going to talk about the cause of running related
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  injuries. Despite changes in shoe
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  technology, training programs, healthcare coaching, and other
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  factors, the rate of running related injuries has remained
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  stable for decades. As humans we crave a single
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  solution, and as runners we talk about this in ways that reflect
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  this desire. Maybe I'd in different shoes,
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  maybe you're running too fast, maybe you're not running fast
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  enough, maybe you need more cross training, and many other
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  strategies likely permeate the post run conversations of your
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  running group. Sadly, we know enough to know a
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  single solution won't fix the multifactorial problem of
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  running related injury. In 2017, Michael Bertelsen and
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  colleagues at our house university in Denmark published
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  A framework for the etiology of running related injuries in the
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  Scandinavian Journal of Medicine and Science and Sports.
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  The model explaining the cause of running related injuries
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  makes a ton of sense. I'm going to describe the model
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  and give some examples of how it applies to running related
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  injuries. Then I'll share thoughts on
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  strategies to decrease someone's risk for injury, and we'll also
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  describe some strategies for how we can use this model to make
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  informed training decisions. And injury will occur anytime
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  the imposed load exceeds a tissue's capacity to withstand
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  that load. The imposed load can be from a
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  single event, as we witness when we watch a sprinter sustain a
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  hamstring strain on a single stride or a bone is broken
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  during a single fall. Here, the imposed load of that
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  single event exceeded the tissues capacity to not be
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  injured and withstand that load. Alternatively, the injury could
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  occur from an accumulating accumulating multiple loads that
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  then exceed the tissues tolerance over time, even though
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  no single load could cause an injury.
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  Bone stress injuries and tendon problems are common running
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  related injuries that recurred due to recurrent micro trauma.
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  The framework is a visual model so I want you to mentally
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  picture three boxes. Two small boxes are stacked on
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  top of each other on the left side that represent the load
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  capacity of a tissue. This could be any tissue, but
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  bone, tendon and muscle are common tissues that have running
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  related injuries. The box on the top represents
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  the tissue specific capacity entering a training session.
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  So when you're when you're on your training begins.
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  The tissue capacity to accept load at the moment the training
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  session begins is influenced by many things such as age, your
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  genetics, the tissue type, the general health status that you
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  have, or any other prior injuries that you may have
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  experienced previously. None of these factors can really
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  be changed. The modifiable things in this
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  upper left box representing the tissues ability to withstand the
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  load include prior training, your sleep, your diet, and the
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  time since your last training session.
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  These are modifiable things that athletes and coaches control
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  that influence the tissues ability to withstand the load of
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  the training session. Coaches and athletes think about
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  many of these things, maybe all these things already in their
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  training and and coaching activities, but the fact that
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  the tissue's ability to tolerate load is influenced by factors
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  that are both modifiable and non modifiable.
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  The non modifiable being like your genes and your age or prior
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  injuries. They partially explain why 2
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  seemingly similar athletes, similar athletes have different
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  load tolerances or different injury resistance.
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  The lower box on the left side is the reduction in tissue
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  capacity that occurs during a training session.
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  In most training sessions this isn't a huge factor, but it is a
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  real world factor that will be in one of the examples that I
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  give you later. So the left side of your mental
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  diagram should have stacked boxes representing load
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  tolerance or the tissues capacity to withstand the load
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  imposed by running. The top box is the tissue's
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  capacity at the start of training and the bottom box is
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  the reduction in load capacity during the training session.
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  Could also think of that as fatigue.
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  The single large box on the right hand side contains all the
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  factors that contribute to the cumulative load during a
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  training session. There are four parts inside this
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  box. The magnitude of load on each
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  stride is determined by body weight, running speed, terrain,
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  and also running form. This is one of the four parts in
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  the box on the right. The distribution of load in each
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  stride is the second part of in the box on the right, and the
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  distribution of load on each stride is determined by the body
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  composition, body shape, running form, footwear, and running
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  surface. The third part in this box, the
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  load to applied to each specific tissue during each running
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  stride. The load applied to each tissue
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  is determined by the 1st 2 parts, which is the amount of
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  load per stride and the distribution of that load during
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  each stride. It's impossible to really know
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  the structure specific load on every stride.
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  The variability in per stride load likely explains why certain
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  runners seem to be struggling with certain injuries.
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  The 4th and final part in this large box on the right hand side
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  of your mental diagram is the number of strides taken during
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  the training session. I don't know anybody who counts
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  the number of strides they take during a training session.
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  However, running distance, running duration, or training
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  volume are often tracked by runners and coaches, and many
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  runners track training volume very, very carefully.
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  The number of strides in the load applied to each stride
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  determine the cumulative load a specific tissue experiences
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  during each training session. Now imagine the boxes on the
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  right and left as if they're sitting on a teeter totter.
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  If the load of a training session outweighs the tissue
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  capacity and injury will occur, the right side of your mental
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  diagram will weigh more. If those training loads exceed
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  the tissue's capacity was drawn and the the right side will win.
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  If the tissue's capacity to tolerate the load or those
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  things on the left side is not exceeded, the left side of your
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  mental diagram will outweigh the training load and the athletes
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  going to remain healthy. If recovery is insufficient, the
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  right hand side will gradually outweigh the tissue tolerance on
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  the left hand side with an injury developing when the
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  tissue can no longer withstand the training loads.
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  Now let's go through some examples to to help this mental
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  model come to light in some real world examples.
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  So here are some track and field examples.
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  In the first one, a sprinter pulls up with a hamstring strain
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  during the maximum velocity phase of a race.
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  It's a devastating sight. We've all seen it and I, I don't
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  know about you, but it always just sort of hurts in my soul
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  when I see sprinters at at top end velocity get injured before
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  the end of the race. In those moments, the muscles
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  injured because it cannot produce the necessary force to
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  slow the leg segment, the part below the knee in a terminal
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  phase, terminal portion of the swing phase.
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  Excuse me, I often wonder why that stride was the moment of
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  injury. These athletes had remained
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  healthy when sprinting at Max velocity in other races.
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  In other practices, they may have even been running at Max
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  velocity in the previous few strides.
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  But for whatever reason, that was the stride that did it.
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  The tissue tolerance at that moment was insufficient to meet
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  the required force demands and the load exceeded the tissue
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  tolerance. Sometimes we've seen athletes
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  experience this type of hamstring strain injury late in
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  the Sprint. Race fatigue or also consider
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  the decline in tissue tolerance that occurs during the race may
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  be the explanation in that particular situation.
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  This example shows how load can acutely exceed a tissue
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  tolerance and how we may observe injuries that result from the
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  decline of tissue tolerance during the running session.
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  An alternative example are bone stress injuries or stress
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  fractures. These are an examples of an
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  injury that occurs from accumulative accumulated load
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  over time rather than a single event.
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  Bone stress injuries occur when the frequency of loading
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  outpaces the bones ability to regenerate or heal from the
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  imposed load. Overall, bones are a highly
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  adaptive tissue with really good regenerative capacity.
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  When a bone is broken, it typically heals and the healed
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  bone is extremely similar. Similar to the bone prior to the
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  injury, bones actually require load to stimulate bone
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  formation. However, the cumulative load per
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  running session will result in small levels of bone damage that
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  heal between running or other sport training sessions.
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  With insufficient time to recover, the bone progressively
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  accumulates damage until a bone stress injury occurs.
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  Reduced loading for a sufficient amount of time allows the bone
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  to heal, and this bone stress injury example shows how
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  acceptable loads in the right boxes may still lead to an
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  injury if the tissue's ability to withstand those loads is
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  insufficient. Now I'll briefly share some
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  strategies. I'm going to share additional
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  strategies and be more specific in some recommendations that I
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  make for other Gill 1918 podcasts.
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  This is an unsponsored plug to follow the Gill Connections
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  podcast so you know when any new episode comes out.
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  I believe athletes are primarily responsible for the tissues
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  capacity with stand load imposed by running or the upper left box
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  in the mental image you you created.
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  An athlete optimizes their ability to tolerate training
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  load with sufficient sleep, a diet to provide adequate energy
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  availability and attention to rest.
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  Coaches can advise and recommend, but it's really up to
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  the athletes to follow through on this part.
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  Coaches have the the primary responsibility in the right box
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  that contributes to the cumulative load to the tissue as
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  a result of training. Thoughtful, purposeful training
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  plans with graded progression of training duration and intensity
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  should aim to optimize training stimulus while mitigating injury
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  risk. While the coaches who write
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  training workouts or training plans take the primary
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  responsibility, it's critical for athletes to adhere to the
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  training intent. Athletes who run hard on easy
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  days, add extra training beyond the session plan, or otherwise
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  do not adhere to the planned training risk injury because
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  they may exceed the tissue load. The running world has primarily
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  focused on distance and intensity. 1 researcher
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  described this as distance runners having a deep
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  infatuation with running volume. He was probably right.
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  The running community and track and field culture primarily
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  track and make our training decisions based on running
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  volume and intensity. These are only two of the four
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  parts in the right box of our mental diagram.
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  Running form, or more specifically changes in running
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  form, influence how loads are distributed across tissues
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  during each stride and may potentially influence the
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  magnitude of load for each stride.
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  Considering changes to running form in combination with running
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  volume and intensity produce a decision making pattern that
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  considers all four parts that determine the load per running
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  session. I'd encourage you to listen to
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  the Guild 1918 episode number 15 where I discussed step rate as a
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  teaching tool. If you want to learn more about
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  a simple way to adjust running form.
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  Now, the framework I described provides a way to
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  comprehensively think about the cause of injuries.
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  Does not give a formula to avoid injuries.
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  Injuries will occur because it's impossible to determine exactly
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  how much load is being applied to each body tissue or what that
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  specific tissues fatigue point will be.
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  As competitive athletes push their training in a quest to
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  advance their performance, training will result in
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  injuries. However, I believe we should use
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  what we know to avoid injury, delay injury, hasten recovery
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  from injury, or lessen the injury severity.
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  We should use our our knowledge to achieve these goals.
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  I want to make another Gill 19 episode 1918 episode to talk
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  about interventions that will increase the load capacity for
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  specific tissues. But for now, let's focus on the
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  framework for injuries and the things we've talked about today.
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  My name is Evan Nelson and I'm the director of the Velocity
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  Project. I started the Velocity Project
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  because as a runner, running researcher, physical therapist,
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  youth sport coach and parent, I want the science of running to
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  positively impact athletes. The Velocity Project mission is
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  the seminate evidence based knowledge to enhance health,
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  performance or experience for youth track and field athletes.
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  This is my research line as a professor at the University of
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  Wisconsin, and we want to share research from us and from other
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  researchers and other places specifically that focus on high
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  school runners. We want to provide high school
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  coaches with knowledge and resources to implement new
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  knowledge into their practices. If you want to see our work or
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  learn more about what we're doing, follow us on social media
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  on Instagram or wisco dot velocity.
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  That's WISCO dot velocity. We're also the Velocity project
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  on Facebook or LinkedIn. Our project website is Velocity
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  project all one word at fammed.whisk.edu.
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  That's velocity project all one word fa.fammed.wisc.edu.
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  Or listen to our podcast called Science on Track, which is
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  available on Spotify, Amazon, Apple, or your favorite podcast
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  platform. I'm happy to connect with you at
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  any time. I love talking about running,
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  running injuries and even more preventing running injuries.
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  So thanks for listening to this episode.
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  I hope you'll turn tune into other Gill 1918 episodes that
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  that we make. Thanks a lot.
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  Hey gang, Mike Cunningham here. Hey, I hope you enjoyed this
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  episode of the Gill 1918 Project series.
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  It's really my mission, my passion to bring you massive
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  amounts of value and I hope this one hit the mark.
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  The Gill 1918 Project is really dependent on you if for you to
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  build your own episode, to hear your voice, to have your voice
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  heard you have something to say and teach other coaches out
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  there. So please get a hold of me,
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  E-mail, text message, Twitter, smoke signals, get a hold of me
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  and let's help create your episode of the Guild 1918
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  Project. Hope you enjoy the day, they
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  will see you tomorrow.