Low vs. High Threshold Strategy

Understanding the difference between low and high threshold strategy is a very important part of rehab and training.  If a patient is using the wrong strategy for the task they will not only be inefficient, but they can make the injury worse and cause more harm.Unfortunately, this has happened to all of our patients at one time or another.  We give them a simple exercise like single leg balance, look away for a second, and turn back to see them holding their breath and violently flailing their arms to keep their balance.  They're not developing stability, they're just using a dysfunctional high-threshold strategy to teach their body how to compensate with the wrong muscles.If you understand the difference between the 2 strategies, you can prevent this from happening to your patients.

Quick Definitions:

Low-Threshold Strategy: Slow, tonic, local stabilizer, stabilizing muscle contractions that are for low-load tasks and reflexive postural control.  This is necessary for joint centration.High-Threshold Strategy: Fast, phasic, prime mover, global mobilizer, mobilizing muscle contractions that are for high-load tasks and force production.  This is necessary for strength training.

5 Major Points

1. The difference between high and low-threshold is one of the most important parts of the exercise continuum
2. Low-Threshold must occur prior to High-Threshold to stabilize and centrate the body
3. High-Threshold is necessary, but can become dysfunctional with poor training strategies
4. Assess for threshold strategy by looking at breathing, posture, and alignment
5. Build programs to encourage a fundamental low-threshold strategy before starting high-threshold exercises

Motor Units & Threshold Strategies

Motor Unit

High and low threshold strategy refers to the type of motor unit activity driving a task.  These motor units are responsible for muscle contractions.  The type of motor units recruited for a task are based on many different factors including: muscle fiber type, role of muscle, motor pattern, firing rate, and recruitment threshold.

Threshold Strategies

It's important to understand that most local stabilizing muscles have a higher portion of low-threshold motor units, where as global moving muscles have a higher portion of high-threshold motor units.  Further more, motor units are recruited sequentially from low to high.  It's the body's way of being efficient and trying to perform a task with the easiest motor program possible.  So before high-threshold motor units are recruited, all of the other motor units must be recruited (high-threshold on top of low-threshold).  This increases the mechanical advantage of the global movers and centrates the joint, thus making it more efficient to perform the task.

• Low-Threshold Strategy MUST be recruited before High-Threshold Strategy.

Exercise and Thresholds

To put it in perspective you can look at single leg balance.  You should be able to stand on one leg using a low-threshold strategy.  However, if you add medicine ball throws or step-ups to a single leg stance you are going to have to use a high-threshold strategy on top of a low-threshold strategy.  A low-threshold strategy alone is not strong enough to create enough force to throw a heavy medicine ball.

Low-Threshold & High-Threshold

Before you go crazy trying to label each movement and exercise, it's important to note that this is a continuum.  Not every movement is going to be exclusively one type of motor strategy. 

Low-Threshold

Working within the edge of ability and gaining fundamental stability is paramount for developing efficient stability and power.  Unfortunately many clinicians and trainers overlook this low-threshold motor strategy.Here's an example.  I had an acute low back patient who was deadlifting 350 pounds.  He could touch his toes, passed the ASLR test, his hips were strong, and he could hold a plank for hours.  But when I took him through some low-threshold developmental stability patterns he started shaking all over the place.  After he developed some low-threshold stability he went back to pain-free deadlifting and improved his PR by 20 pounds in the next month.  It's not always this extreme, but shows a great example of how joint centration goes beyond rehab.So there are 2 ways you can sell this to your patients:Optimist: If you are really strong without a low-threshold motor program, then imagine how much stronger you would be with one.Pessimist: If your strong without a low-threshold motor program, then all you did was strengthen your compensations and poor movement patterns.

High-Threshold

Some people use the term high-threshold strategy to define a dysfunctional motor strategy.  I feel that this can be a little misleading and give high-threshold motor patterns a bad rap.  If athletes didn't use high-threshold strategies they wouldn't be able to accomplish the amazing physical feats we see on Sports Center's Top 10.  And without high-threshold strategies our Top 10 would just be a bunch of trick pool shots and geriatric shuffleboard.

What Goes Wrong?

The body moves very efficiently when the low-threshold precedes the high-threshold.  It's when people skip the low-threshold step that things start to go very wrong.  This dysfunctional high-threshold only strategy will plague the body compensations and inefficient movement.When the body fatigues and the local stabilizers stop firing, the body goes into a dysfunctional high-threshold strategy.  This is filled with poor movement patterns.  To make matters worse, it teaches the body how to incorrectly use global mobilizing muscles (as movers AND stabilizers).  So now these muscles are always on and always trying to do everything, even for low-load activities.Just like anyone that is worked twice as hard, these muscles get very unpleasant.  They lock up, have overdeveloped tone, become fibrotic, have decreased blood supply (from being contracted all the time) and become over facilitated.Cranking on these muscles may provide temporary relief.  But to solve the problem you need to go to the low-threshold strategy that isn't firing.  Other wise the viscous cycle will continue. 

High-Threshold Strategy is a Dysfunctional Pattern When:

• Used in Substitution of Low-Threshold
• Cannot Turn Muscles "Off" (Results in Splinting, Not Stabilizing)
• Global Mobilizing Muscles Have to Move AND Stabilize
• Places the Body in Poor Alignment / Posture
• Sacrifices Mobility for Force Production

So how do you assess for which strategy is being used?

The simple answer is breathing.  99% of the time breathing strategy it will match up with their threshold strategy.The Threshold-Breathing-Continuum:  Parasympathetic diaphragm breathing is used in low-threshold strategies.  Breath holding and valsalva is used in high-threshold strategies.

• Assessing Breathing = Assessing Threshold Strategy

Another give away for dysfunctional threshold strategy is poor alignment/posture.  If someone can't use a low-threshold strategy they'll compensate with a high-threshold strategy and the global mobilizing muscles will pull the body out of optimal positioning (centration).

So What Do You Do Now...?

FMS Performance Pyramid

The FMS Performance Pyramid provides a great picture of how to balance your plan of care (or training) in terms of human performance.  Much like the low before high-threshold principle, this pyramid emphasizes the fundamental mobility balance, and coordination.

My Threshold Pyramid

It's important to first consider mobility before threshold strategies.  Mobility and tissue quality is a priority before stability and movement.  Trying to force patients through mobility deficits will only feed into their movement pattern dysfunction.  Once you have resolved or made a change in their mobility, you should then move towards threshold training.Since the normal firing pattern is low-threshold before high-threshold, you should probably train your patients the same way.  To do this, simply make sure your patient can perform low-threshold strategies independent of load, force, or movement.  After this is accomplished you can add in the load, force, or movement and work towards more high-threshold type of strengthening exercises.Once they are efficient with the low-threshold patterns don't throw them away and forget about them.  They're great for warm-ups, CNS resets, starting positions, or active rest.Examples of Low-Threshold → High-Threshold:Core: Soft Rolling → Hard RollingShoulder: Bottom-Up Kettlebell Screwdriver → Single Arm RowsHip: Quadruped Alt UE/LE → Deadlift

Bottom Line

There's already enough to think about when selecting exercises (pathology, movement pattern, biomechanics, kinesiology, anatomy, etc.).  And it sucks to add more to the list.  But if your patient is using a dysfunctional high-threshold strategy the rest of the list doesn't matter.  By keeping tabs on the threshold strategy your exercise prescription will only be more effective.

References

Gray Cook - MovementCharlie Weingroff - Training=Rehab, Rehab=TrainingBryan AusinheilerKevin Neeld --The main reason I do this blog is to share knowledge and to help people become better clinicians/coaches. I want our profession to grow and for our patients to have better outcomes. Regardless of your specific title (PT, Chiro, Trainer, Coach, etc.), we all have the same goal of trying to empower people to fix their problems through movement. I hope the content of this website helps you in doing so.If you enjoyed it and found it helpful, please share it with your peers. And if you are feeling generous, please make a donation to help me run this website. Any amount you can afford is greatly appreciated.

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June Hits

1) So Zac Cupples does Cliffnotes for PT books.  Here's his post on the Sensitive Nervous System by David Butler.  If you aren't familiar with Butler and the NOI approach you should check it out.  "Pain is an unpleasant, sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage."

2) As a deep squat advocate, I loved this post by James Speck.  To perform the deep squat you must have BOTH mobility and stability.  This alone makes it a great assessment and intervention.3) The most important aspect of preventing an acute pain patient from becoming a chronic pain patient is how fast you can get them out of pain.  Erson goes over 5 Rules of Resets for using end-range mckenzie to decrease pain.4)  I don't think she needs hip mobs.5) Brett Contreras loves the glutes.  He's obsessed with the glutes.  So when preferences an article about the glutes as one of the best he's ever written, you should read it.  One of my favorite parts was this gem: "The hip thrust is actually the lower body equivalent to the bench press. It provides three points of support and takes advantage of gravity to work the hips from a horizontal vector."  And as with all exercises, don't knock it until you try it.6) Hamstring strains are terrible.  They suck to have and are even worse to treat.  I feel that the classic eccentric progression doesn't always lead to great outcomes.  Each patient is different and requires different approaches (scar mobilization, neurodynamics, core stability, motor pattern training, glut strengthening, etc.).  Here's 2 articles that can help: 1, 2.7) DNS and powerlifting, what a wonderful marriage.  Here's a great quote from this very Weingroffish article by Todd Bumgardner "Long story short, with your neck extended your brain thinks your spine isn't stable, or safe, and it limits neural drive to outer-core and prime movers."  Consider neck positioning in everyone, not just the cervical patients.[subscribe2]

Quadruped

The quadruped position is a very important developmental posture.  From this posture we learn to crawl and transition to half-kneeling (which then transitions into standing).  Through this posture we develop core, shoulder, and hip stability, learn reciprocal UE/LE motion, and begin to control our spine through our weight-bearing extremities.  The quadruped position has many details that are often lost or forgotten when training.  Mastering these subtleties and progressing within the edge of your ability will lead to a great effect on your stability.

What it Does

• Taps into Hard-Wired CNS Developmental Stage
• Increases Hip, Shoulder, and Core Stability
• Self-Limiting Posture
• Challenges Rotary Stability
• Develops Reciprocal Motion & Coordination
• Removes Ankle/Knee Compensations
• Allows for Unloaded Spinal Stability

3 Keys to Performance

1. Maintain Neutral Spine
2. Hips and Shoulders should be at 90 degrees
3. Do not allow any pelvis or shoulder girdle rotation

Common Faults to Avoid

• Hyperlordosis with leg extension
• Compensatory pelvic rotation (usually opening)
• Scapula winging and or elevation on weight-bearing arm
• Non-neutral cervical position (looking forward or cervical protrusion)
• Compensatory weight shift over weight bearing extremity
• High-threshold strategy

Clinical Use

Examination

Using this posture for assessment can determine whether a patient has a weight-bearing stability issue, an open chain compensation, a spinal stability dysfunction, or a combination of these dysfunctions.  Furthermore, it can help determine the specific position of instability (i.e. hip flexion vs hip extension, shoulder end-range flexion vs mid-range flexion).  Determining the specifics of their motor pattern dysfunction can help you further individualize your plan of care.For more advanced and active patients you can take them through a 6 level progression (see video below) to determine their level of stability and determine whether it is a static or dynamic dysfunction.  Make sure to pay attention to any asymmetries, compensations, or faults.http://www.youtube.com/watch?v=kK0-jpxMbos

Intervention (Train the Brain)

A proper assessment leads to a more effective intervention.  By taking the patient through the 6 level quadruped progression you can determine the limits of their ability.  Once you determine this you can train them within their edge of ability to improve their stability.  It's important to avoid compensations or making the exercise too difficult.  This should be a low-threshold training exercise.  Think about training the pattern instead of the muscles.After mastering the 6 levels of quadruped stability you can further add other extremity movements, resistance, or perturbations to make the exercise more difficult.  Many clinicians and trainers even use creeping, crawling, and even the bear crawl for exercise progressions.

Summary

The developmental perspective shows us that movement was developed in patterns, not by isolated muscle strengthening.  Using developmental postures can help to re-wire dysfunctional movement patterns.  Before progressing to more complicated postures (half-kneeling, single leg stance), make sure your patient is efficient in this quadruped position. --The main reason I do this blog is to share knowledge and to help people become better clinicians/coaches. I want our profession to grow and for our patients to have better outcomes. Regardless of your specific title (PT, Chiro, Trainer, Coach, etc.), we all have the same goal of trying to empower people to fix their problems through movement. I hope the content of this website helps you in doing so.If you enjoyed it and found it helpful, please share it with your peers. And if you are feeling generous, please make a donation to help me run this website. Any amount you can afford is greatly appreciated.

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May Hits

1) "An alteration of the language output may be as clinically potent in desensitising pain neurosignatures and it certainly has not been considered as deeply in rehabilitation."  David Butler discusses how correcting patients language & thoughts relating to their pain is just as important as it is to correct their movement output.  This month's JOSPT has a related article on the how movement system diagnostic labels can prevent the disconnect between diagnostics and treatment processes that pathoanatomic labels create.

2) The hip hinge is one of the most important movement patterns for anyone that moves.  This months article goes over what it is, how to assess it, and how to correct it.

3) Changes in ankle push-off are inversely related to changes in the internal net hip muscle moments.  In other words, there is a tradeoff between the hip and ankle during gait.  Giving your hip patients the cue to walk with more ankle push-off can decrease the load on their hip and improve their function and pain (and vice versa).

4) Charlie Weingroff has a nice blended lens of SFMA, DNS, and strength and conditioning.  Here's 34 great quotes that you can apply in the clinic today.  One of my favorites "If you want to fix your posture, I want you to feel wrong. Then, when you feel wrong, you can start to feel right."5) 25 Things you can learn from one of the best trainers around - Mike Boyle.6) Integrated core exercises proved to have much higher muscle activation that isolated core exercises.  The integrated exercises were movement that caused co-activation of core muscles coupled with hip and shoulder activation.  The study concluded that "when completing the core strength guidelines, an integrated routine that incorporates the activation of distal trunk musculature would be optimal in terms of maximizing strength, improving endurance, enhancing stability, reducing injury, and maintaining mobility."  SMR has a review of it here.7) Knee valgus collapse can be one of the most abrasive movement dysfunctions to the lower extremity.  James Speck has a great article that sums up this dysfunction and how to fix it.

Hip Hinge

The hip hinge is a basic movement pattern that everyone must have.  When people have atrophy of this movement pattern they end up compensating in all sorts of ways (trendenlenberg, dynamic valgus, knee dominant movements, lumbar flexion).  This leads to decreased performance and increased risk for injury.

Why Hip Hinge?

If you want to truly load the hips then you have to know how to hip hinge.  The hip hinge is a hip dominant movement that is the basis for most athletic movements.  Sure, there needs to be a baseline level of strength at the hip joint.  But you can't really think clamshells and side steps are going bring your patients back to their highest activity level.Even if your patient isn't an athlete, they need to hip hinge.  Everyone has to do it, and has been able to do it at least at one point of their life (it's part of the developmental progression).  Furthermore, it's used for basic life movements.  The hip hinge is how you should be picking objects off the ground, it's how you should go from sit to stand, it's how you should move furniture, it's how you should do most activities throughout the day.

Hip Progressions

The basic progression for most strengthening exercises in rehab is to go from isolated isometrics to basic isotonics to dynamic movement patterns.  Seems pretty simple, right?  However, many PT's miss this last part.  This is where "bridging the gap" happens.  If you have your patients doing clamshells with black thera-bands and sidelying hip abduction with 10 pounds and you haven't started hip hinging, then you are probably wasting everyone's time.By working on your patient's hip hinge movement pattern you will not only be sparing their knees and backs, but you will be giving them a movement pattern that they can load up as much as they want for the rest of their lives.  They can either keep it as a basic ADL movement (sit-stand, picking up objects) or they can load it up to deadlift hundreds of pounds, crush a golf ball 300 years, explode past that pesky defender, or blast a forehand down the line.  Regardless of what you think your patients can do, it's best to leave them the option to choose themselves.

What is a Hip Hinge?

A hip hinge is a posterior weight shift through the hip joint.  It's a sagittal plane moment where the hips become the axis between the upper and lower extremity through a neutral spine.Hip hinge is the basis for most hip movements.  Developmentally we progress from the sagittal, to the frontal, to the transverse plane.  Since the hip hinge is the most basic and dominant sagittal plane motion for the hips, it is the best place to start movement patterns.  Before you start developing stability in the frontal and transverse plane, it is paramount to master the sagittal plane first.

Why it's Good

Loading up the hip and developing some serious strength and power is a great advantage of the hip hinge.  But it also has many advantageous effects throughout the body.

Benefits of Hip Hinge:

1. Maximizes the posterior chain
2. Decreases anterior chain dominance/stress
3. Spares the knees and spine
4. Allows for kinetic transfer of energy/force to the upper body

Hip Hinge vs. Squat

Before you teach the squat or the hip hinge, it is important to first understand the difference between the two (videos: hip hinge, squat)The deadlift is hip hinging at it's best.  So we will use it as an example in this comparison.If you are new to the deadlift and sqaut or have difficulty determining which movements are clinically hip dominated vs. knee dominated you can use this formula:Hip Dominated (Hip Hinge) = Vertical Tibia + Posterior Pelvis Movement + Moderate Trunk LeanKnee Dominated (Squat) = Angled Tibia + Inferior Pelvis Movement + Minimal Trunk Lean

Hip Hinge (Deadlift)

The hip hinge, as it implies, is a hip dominated movement.  It is a much simpler movement than the squat.  You really only use one part of your body (hips) to "push the ground away".  The main joint movement afferent input your brain has to deal with is in the hips, knees, and spinal angle.  An oversimplification of the physical requirements include: posterior chain activation, posterior chain mobility, spinal stability, reactive scapula retraction.

Kinematics

• Moderate Trunk Lean
• Pelvis Moves Posteriorly
• Hip Flexion
• Minimal Knee Flexion
• Tibia Remains Vertical

http://www.youtube.com/watch?v=lGAkXEd-bo0

Squat

The squat is more of a knee dominated movement.  However, it's not that simple.  It's much more complicated movement than the hip hinge.  It requires stability of all 3 planes and involves much more motion throughout the body.  You are "pushing the ground away" using 3 body parts (ankle, knee, hip).  The addition of 2 more joints to the motion makes the movement much more difficult to perform.  This additional afferent information will require equal efferent information to adequattely control the joint motion.  An oversimplification of the physical requirements include: anterior chain stabilization to maintain upright posture (core, hip flexors, anterior tibialis), significant ankle, knee, hip, & thoracic mobility, multi-segment eccentric control, and maximal triple-extension activation.

Kinematics

• Minimal Trunk Lean
• Pelvis Moves Inferiorly
• Deep Hip Flexion
• Deep Knee Bend
• Tibia Moves Anteriorly

https://www.youtube.com/watch?v=C-kKvNwJ1Uc

Assessment

I tend to use 4 movements to assess a patients ability to hip hinge: SFMA Multi-Segment Flexion, Quadruped Rocking, Hip Hinge with Dowel, and Squat.SFMA Multi-Segment Flexion: The sagittal plane should be the first movement you check in every patient.  If they can't master the sagittal plane, they'll compensate in another plane.  Don't chase your tail trying to fix a rotational problem when it's really a sagittal problem that compensates in the transverse plane.  Now I'll step off the soap box...MSF requires a posterior weight shift to touch toes.  If you patient can't touch their toes or doesn't posterior weight shift, then hip hinging will serve them well.Quadruped Rocking: This isn't just a childs pose test for lumbar flexion.  You are checking their ability to sit back into their hips in an unloaded position.  To perform, have them go into neutral spine and rock back as far as they can without losing their lumbar position.  If you patient can't maintain neutral spine (i.e. they go into flexion) while going into hip flexion then hip hinging is a good option.Hip-Hinge with Dowel: This exercise can give you a great view into their movement patterns and possible physical impairments.  It's best not to coach this and give alot of cues.  Simply perform the movement yourself, then ask them to repeat it.  Try to assess their movement pattern and associated compensations.Squat: The squat is complex and there can be many different impairments that prevent functional movement.  But if the patient cannot get their hips below parallel then the chances are they are so quad dominated that they can't shut them off to sit into their hips.

Intervention

There is no clear cut protocol and way to teach the hip hinge.  This is probably why there's no research on the movement pattern.  There are just way too many variables (in the patient, in the movement, in the exercises) to try to standardize in a study.  But this is a good thing if you are willing to put in the time and effort.  There are three main things you can control: the progression, the verbal cues, and the visual props.

Progression Continuum

The most important aspect of the progression is that you want to make sure your patient has mastered the movement pattern before you load it.  This is where most people go wrong.  They load the up deadlift with too much weight or start patients with single-leg deadlifts when they don't even have the pattern down.This is the clinical progression I have developed over the past couple years:Determining where your patient should start may take some time.  It's always better to have the exercise be too easy and progress them rather than have it be too difficult and frustrate and/or hurt them.

Verbal Cues

You don't want to cognitively overload the patient right off the bat.  I simply tell them to push their hips back without letting the knees come forward.  After I assess their movement pattern I will adjust the cues appropriately.  Other cue's I often use:"Push hips back" - "don't lock out knees" - "reach down and touch your knees"-  "allow knees to bend and go along for the ride" - "keep chest up" - "keep hips down" - "keep a double chin" - "act like you are taking a bow" - "stand tall at top" - "come all the way through with your glutes"

Props

Just like the verbal cues, you don't want to overload them and make them more focused on the props than the movement.  The initial movement pattern assessment determines which props I use.  Depending on each patient you will have to alter your props.  The one I find most useful and most beneficial for beginners is placing a stool in front of their knee (see video below).  This prevents any anterior translation of the tibia.  The good thing about a stool vs. an object that doesn't move is that when the patient gets feedback they will be forced to intrinsically stop the knee moving forward instead of an extrinsic stop where the patient just jams the tibia against a bench or wall.http://www.youtube.com/watch?v=xsjYQ6KBhwsOther common props (and what to use them for):Dowel (neutral spine) - Facing Wall (prevent excessive trunk lean) - Wall Behind (encourage posterior weight shift) -Bench (vertical tibia) - Plinth/High Box (target for posterior wt shift, partial reps) - Limited Weight Landing Area (prevents anterior weight shift)

Common Problems

This is some basic troubleshooting to consider when people are having difficulty with this movement pattern.  Remember, all of this stuff is not black and white.  It's a continuum.  It's usually not as clear and easy as categorizing patients into one pattern.  Some people may have a blend of all of these.  Hopefully this will at least give you a place to start.

1) Inability to Posterior Weight Shift (sit back)

= Decreased Hip Mobility, Decreased Posterior Chain Extensibility

2) Loss of Spinal Curve (hyper or hypolordosis)

= Weak Core, Inability to Stabilize Torso, Inability to Dissociate Spine and Hips

3) Excessive Anterior Tibial Translation, Stopping Short of Full Extension,  Too Much Inferior Movement

= Quad Dominated Pattern, Anterior Pelvic Tilt

Here is a video example of faults #2 & #3.

Bottom Line

The hip hinge movement pattern is essential for anyone that moves.  A loss of this movement pattern can lead to many deleterious effects.  By training the movement pattern you will give your patients the ability to perform ADLs and athletics without compensations and increased risk for injury.  Once your patient has the hip hinge down they can either simply maintain it for health and injury prevention, or use it to truly load the hips and build some athletic power.Isolated isometrics and basic isotonic strengthening exercises are necessary.  But to take our profession to the next level (and your patients) we need to "bridge the gap".  Try adding some movement training into your plan of care.  Your patients will appreciate it.Hopefully this article will give you an idea of how to integrate this into your practice.  And with every exercise you prescribe, try it yourself (but don't be this guy).

Dig Deeper

Christopher Smith - Squat vs. DeadliftEric Cressey - Mastering the Deadlift (check out all 3)DragonDoor - Deadlift for Body TypeDan John - Hip HingeT-Nation Deadlifting - 1, 2, 3Bret Contreras - Sumo vs Conventional, EMG Muscle Activation

Mike Robertson - Deadlift

Schwarzenegger - Deadlift

Tony Gentilcore - Coaching Cues

Jeff Kuhland - Hip Hinge

Anything by Chris Powers - it might not be intentional, but much of his research is basically on the hip hinge pattern

--The main reason I do this blog is to share knowledge and to help people become better clinicians/coaches. I want our profession to grow and for our patients to have better outcomes. Regardless of your specific title (PT, Chiro, Trainer, Coach, etc.), we all have the same goal of trying to empower people to fix their problems through movement. I hope the content of this website helps you in doing so.If you enjoyed it and found it helpful, please share it with your peers. And if you are feeling generous, please make a donation to help me run this website. Any amount you can afford is greatly appreciated.

 [subscribe2]

April Hits

1) Beighton Laxity Scale gives a good indication of your patients congenital laxity.  If your patient is extremely hypermobile then you shouldn't be spending alot of time doing joint mobilizations and/or manipulations.  These patients require a great deal of stability.

2) Davis' Law, the soft tissue equivalent to Wolff's Law, describes how soft-tissues adapt to stress.  It describes how muscles adapt in a reciprocal manner.  For example, a strong and inflexible gastroc will usually cause the anterior tibialis to become weak and flexible.  With this law in mind, you should always consider the antagonist when trying to achieve an increase in strength or mobility.

3) James Speck goes over forefoot varus and over pronation.  You can have some success lumping patients into either supinators or pronators, but if you really want to fully assess your patients you need to know about structural foot deformities their associated pathomechanics.

4) Erson goes over 5 ways to improving the deep squat. 1.Diaphragm breathing 2. Taping 3. Rolling 4. Hip Stability 5. Scapular/Cervical Stability.

5) Why we'll always have job security.6) Eric Cressey always puts out quality stuff that you can immediately use.  You can teach your patients this or work on it yourself.  6 tips for people that stand all day.7) The step up is a great exercise.  However, many people hack it up and bypass all the benefits.  I find many patients tend to shift their weight too far forward, use quad dominant form, can't sit back into their hip, and have excessive trunk lean.  To clean this up try this counter-balance method.

Pathomechanics of the Foot

Separating foot types into supinators or pronators may provide adequate assessment for treatment.  

However, for a more specific treatment plan it would be advantageous to understand the possible abnormalities and pathomechanics of the forefoot and rearfoot (calcaneus).  

More importantly, knowledge of these abnomalities/pathomechanics will also prevent deleterious treatment.

For example, providing medial calcaneal mobilizations/releases for the overpronator would be great if the patient has a compensated calcaneal varus.  But if the patient has a compensated forefoot varus the medial mobilization/release would likely worsen their injury.

It may sound complicated, but once you understand these 3 foot abnormalities and pathomechanics it will make sense.

Foot Pathomechanics = compensations that occur from foot abnormalities during weight bearing tasks

The 3 Foot Abnormalities

1. Calcaneal (Rearfoot) Varus

2. Forefoot Varus

3. Forefoot Valgus

Basic Foot Knowledge

The foot can be simplified into a structure that has 2 jobs: mobility (pronation) and stability (supination).  

It requires adequate mobility to adapt to ground surfaces and facilitate shock-absorption.  It requires stability to function as a rigid lever for efficient propulsion.  Failure of either of these jobs will cause great dysfunction throughout the body.

This stability and mobiilty is dependent on an intricate passive and dynamic system.  

The passive system of bone orientation and joint congruency help to provide static stability when aligned, and flexibility when not aligned.  

The dynamic system of the muscles help to reinforce stability and allow for controlled flexibility (eccentric loading).  

When there is an abnormality in the foot alignment or structural, the subtalor joint often compensates by altering the normal balance of stability and mobility.

Treating the compensation may provide the patient relief.  But for full resolution of the dysfunction you will need to correct and remove the cause.

Normal Foot

Normal neutral foot alignement is compromised of 3 things:

1) Neutral Subtalor Joint

2) Vertical Calcaeus (in line with lower leg)

3) Metatarsal Heads Perpendicular to neutral calcaneus/subtalor joint.  

This is the position for optimal functioning of both passive and dynamic systems.

Assessment

Postural assessments should be viewed from all angles.  An anterior view will show any sagittal plane deviation (forefoot abduction). An oblique view will give a good assessment of the arch and navicular hight.  A posterior view will display calcaneal and subtalor positions.

Once you have a postural assessment, it is important to determine the foot alignment and structure.  There are many ways to accomplish this.  Finding talor neutral (anterior palpation), lower leg to rearfoot alignment, unbiased passive dorsiflexion, joint play, postural foot assessment, and gait analysis.  

I find it best to use a combination of these assessments.  If you understand the possible types of pathomechanics and forefoot/rearfoot alignment it will make it easier to determine exactly which foot type your patient has.

Finally, you want analyze their gait to see how the patient dynamically uses their foot alignment and structure.  The static postural foot assessment will help give you an indication of what you should be looking for during the analysis.  

You want to not only look for over or under pronation, but try to assess for 3 specific aspects of the dysfunctional motion (compensation).  This is of paramount importance because it is the compensations that will dictate which structures you need to treat.

3 Aspects of Dysfunctional Motion

• Amount of Motion

• Speed of the Motion

• Timing of the Motion

Calcaneal (Rearfoot) Varus

This is the most common foot abnormality.  However, it may or may not be a clinical problem.

Calcaneal/Rearfoot varus is when the calcaneas is inverted with the subtalor joint is in neutral and the forefoot is perpendicular to the lower leg.  

This foot abnormality is more supinated at heel strike.  These patients often present with decreased lateral (eversion) subtalor joint play.

Compnesations include overpronation or 1st ray plantarflexion to allow the medial forefoot to contact the ground.

Posture Assessment

Uncompensated

Calcaneus Inverted & Navicular Raised = Supinated

Compensations: Distal = Plantarflex 1st Ray, Proximal = Varus Tibia

Compensated

Calcaneus Vertical & Navicular Collapse = Pronated

Gait Assessment

Abnormal compensatory pronation (amount & speed) will occur at heel strike and continue until heel rise.  After the heel is off the ground the foot is able to supinate in time for a fairly normal propulsion.  

These patients differ from forefoot varus in that the calcaneus does not go into excessive valgus (eversion).

http://www.youtube.com/watch?v=5GYI8zA-Rz8

Forefoot Varus

This is the most destructive foot abnormality to the lower extremity.  Because of this, it is the most clinically common pathomechanical abnormality.

Forefoot varus is when the forefoot is inverted (big toe higher than 5th toe) while the subtalor joint and calcaneus are in neutral.  This foot abnormality almost always causes over pronation.  Joint play is often excessive.

Compensations include calcaneal eversion and navicular collapse to allow forefoot to contact the surface.

Posture Assessment

Uncompensated (very uncommon)

Calcaneus Vertical & Navicular Raised = Supination (lateral foot weight shift, 1st ray off ground)

Compensated

Calcaneal Valgus (everted) & Navicular Collapse & Forefoot Abduction= Pronated

Gait Assessment

To allow for the inverted forefoot to contact the ground there is excessive compensatory pronation (amount & timing) beginning at the foot flat phase of the gait cycle.  This continues for the rest of the stance phase, causing the patient to push-off with an unlocked pronated foot.  

This is a major clinical problem since push-off requires a rigid supinated foot to use as a lever for propulsion.  These patients differ from calcaneus varus because they are not able to achieve any supination prior to push-off.

http://www.youtube.com/watch?v=yua1W4GTjAk

Forefoot Valgus

This foot abnormality often presents in patients with rigid and supinated feet (unlike forefoot varus).  Since they are already in a supinated posture they are at higher risk for inversion ankle sprains.

Forefoot valgus is when the forefoot is everted while the calcaneus and subtalor joint are in neutral.  The medial metatarsals lie below the calcaneus (plantar flexed in relation to the calcaneus).  

There are two different types:

total valgus (all the toes slope down)

or 1st ray plantarflexion  

This foot type often presents with restricted joint play (midfoot, 1st ray, calcaneus).

Since the metatarsals lie below the calcaneus it is nearly impossible not to compensate.  The patient must supinate to accomodate this abnormality.  This may lead to a calcaneal varus compensation.

Postural Assessment

Uncompensated

Very uncommon - would cause a significant amount of increased pressure on the first ray

Compensated

Calcaneal Varus (inverted) & Naviclar Raised = Supinated

Gait Assessment

Excessive compensatory supination occurs (amount & timing) after heel strike due to premature loading of the forefoot.

Pronation is insufficient,  but may occur at the end of stance phase to allow for knee flexion.  

This foot abnormality has trouble attenuating loading forces, thus proximal joints are forced to accomodate.

http://www.youtube.com/watch?v=Q0zLo420j2A

Bottom Line

It is important to note that these abnormalities and pathomechanics are not black and white.  They exist on a continuum and are often times combined.  

Being able to further assess your pronators and supinators into a specific pathomechanical foot type will improve your plan of care and allow you to provide your patients with specific interventions to fix the culprit of the problem.

Supinators (Pes Cavus)

Uncompensated Calcaneal Varus & Compensated Forefoot Valgus

Pronators (Pes Planus)

Compensated Calcaneal Varus & Compensated Forefoot Varus

While this post focused specifically at the local foot and ankle joint, it's important to consider regional interdependence.  

Remember that the height and rigidity of the arch can be affected by tibial internal and external rotation (in closed chain).  And this tibial motion is further influenced by it's proximal structures.

Dig Deeper

Running Injuries - Foot TypesPhases of GaitSomastruct - Forefoot Varus - Overpronation - Intrinsic Foot Strengthening - Arch StrengtheningPhysioblogger - Plantarflexed 1st Ray

References

Tiberio D. Pathomechanics of Structural Foot Deformities.  PHYS THER. 1988; 68:1840-1849. (A Must Read)Donatelli R.  Abnormal Biomechanics of the Foot and Ankle. J Orthop Sports Phys Ther 1987;9(1):11-16.Brown LP, Yavorsky P.  Locomotor biomechanics and pathomechanics: a review.  JOSPT 1987;9(1):3-10 

March Hits

1) PT School lays down the necessary foundation to develop your career.  There are many important things that we don't learn in school.  Erson goes over 5 of these things.  I completely agree.

2) This might be a nice progression for patients that have already mastered the sagittal plane and have topped out with isolated hip strengthening (bridges, clamshells, side-step, etc.).  Eric Cressey goes over advanced lateral stability training.3) Chris Johnson goes over the details of how to videotape your runners for analysis.4) Mike Reinold describes his 4 RTC myths in this article.  Mike makes a great point on the importance of simply being strong.  While I am a big advocate of movement pattern training, I agree that there needs to be a baseline level of strength and mobility before focusing on training the pattern.  I often find that weak patients cannot correct their movement pattern in a loaded position without adequate strength of the muscles in the chain.  Many patients require strength training just as much as they require movement training.5) Bill Hartman discusses apical breathing vs apical expansion.  For more information on breathing interventions check out this months post.6) Adrianne Louw once said "I could open up a clinic and call it Left SIJ Dysfunction PT".  He was joking about how most people have a natural asymmetry and discussed the importance of clinical relevance when assessing for SIJ obliquity.  Todd Hargrove goes over a study that proves this.  The study found that the pelvis is often structurally asymmetrical (osseous variance side to side).  Therefore, palpation assessment should not be the sole reason for attacking someone's pelvis with relentless muscle energy techniques.  If you do find a patients whose dysfunction is actually from the SIJ you can try these great techniques provided by Erson.7) I'm not all that interested in the details of nutrition and diet.  Unfortunately, as a result I'm fatter than I want to be.  For those of you who are interested you should check out this article on carb back loading. 

Breathing - Part II - Indications, Assessment, & Intervention

Part I of this series dealt with breathing anatomy and mechanics.  Knowledge and understanding of the anatomy and mechanics of breathing is essential for a proper assessment and intervention.  This post will expand on the previous post and go over some indications, assessment, and intervention for breathing.

Indications

So what type of patients do breathing mechanics apply to?  Pretty much anyone that moves or breathes.Seriously though, you should strongly consider breathing mechanics in all of your patients.  Even if it isn't the main culprit of their dysfunction, it might help return them back to optimal functioning.Some more specific examples:

• Spine, Hip, and Shoulder Dysfunction
• Postural Faults
• High-Threshold Patterns
• Impaired Neurodynamics
• Psychological (apprehension, anxiety, central sensitization)

Assessment

To keep it simple, you want to visually observe their posture and how they mechanically breathe.  Compare this to an ideal breath and look for any signs/symptoms of dysfunctional breathing.  Assess this in various postures (supine, seated, standing) and movements.  The patient doesn't need to know.  In fact, I find it better if the patient isn't aware.  If you do find a patient with a breathing dysfunction you can then go into a more detailed assessment with palpation techniques (discussed under dysfunctional breathing).Sure, you can make it more complicated by assessing breath holding times, questionnaires, and spirometry.  However, this puts the patient through unnecessary discomfort and may affect your rapport.  They walked into your clinic because they're having back pain, not because they want to talk about their breathing patterns and blow into some device.It's important to note that there is a great variance in breathing patterns.  Therefore it is difficult to create a protocol and thorough checklist for an ideal breath.  However, there is alot of evidence for dysfunctional breathing.  So it may be more clinically efficient to look for dysfunctional breathing rather than ideal breathing patterns.

Ideal Breathing

The ideal breath is a smooth, segmental, 3-dimensional motion.  During inspiration there is abdominal distension (circumferentially) and a postero-lateral lower ribcage expansion.  During expiration there is contraction of abdominals and pelvic floor that returns the ZOA to an optimal position as evident by a depressed sternum and IR of ribs (no anterior ribflare).Overall what you're looking for is the inspiratory cascade of events that leads to controlled increased intra-abdominal pressure and proper muscle activation.  On the exhale you want to see adequate expiration of air with no signs of hyperventilation.http://www.youtube.com/watch?v=t0u-bPZrP8g

Dysfunctional Breathing

What you never want to see is excessive accessory muscle activation, disproportionate shoulder movement, T-L junction hinging, or vertical ribcage movement.  Other signs include: mouth breathing, frequent sighs/throat-clearing, rapid and/or shallow breathes, and asynchronous breathsParadoxical breathing is a common breathing dysfunction.  This is when the patient inhales and there is a vertical and posterior motion of the ribcage and a hollowing of the abdominal cavity.http://www.youtube.com/watch?v=8TnrNrrEjuEOne of the biggest signs of dysfunctional breathing is lack of postero-lateral expansion of the lower ribcage.  This can be assessed using the MARM (Manual Assessment of Respiratory Motion).  Research has shown that the MARM can be be a useful assessment for dysfunctional breathing.  This test is simply performed by having the patient seated and facing away from you.  You place your fingers on the lower lateral ribcage and align your thumbs with the spine.  Then have the patient breath naturally while you assess for the postero-lateral expansion of the lower ribcage.  Patrick Ward performs a similar technique in this video around 3:15.

High-Threshold Strategy

This section is purposefully placed between assessment and intervent because it essentially both.  A high-threshold strategy is when an individual performs a task using excessive activity/tone in global musculature in a compensatory or protective manner.  Gray Cook has described it as when "the body is splinting instead of stabilizing".  One of the major signs of this strategy is dysfunctional breathing patterns.An example of this is when you give a patient an exercise that is too difficult for them.  They start to hold their breath and squeeze every muscle they have.  A patient won't be able to perform a proper breathing pattern if they are using a high-threshold strategy.So how do you use this to your advantage?  You can use breathing assessment throughout all of your interventions to verify that the patient is not using a high-threshold strategy to perform the task.

Intervention

There are many ways to treat breathing dysfunctions.  Which rabbit hole you go down depends on your patient and what they need.However, the first place to start for everyone should be from an educational stand-point.  It is advantageous to explain to the patient why breathing is important to them specifically (use knowledge from Part I).  Then you should teach the patient about dysfunctional breathing and what you expect for a proper breath.  To avoid overcomplicating this, I usually simply give the patient a cue that has them focus on the circumferential lower ribcage and abdominal distension.Some example cues I've heard and used: "breath into your lower ribs and abs", "breath into an imaginary belt around your stomach", "breath down and out", "inhale into a balloon inside your stomach", "push your breath down", "expand your ribs out with your breath" etc.  The possibilities are endless.You can also use tactile cues.  Put your hands or a theraband around their lower ribcage to increase sensory afferent input.  Then have them to breath into the resistance of your hands/theraband.For patients who have great difficulty with this or use paradoxical breathing patterns you may need to start simple.  I usually start with a simple progression of hi-lo breathing, lateral expansion breathing, and finally a combination of the two for an "ideal breath".  It's important to educate them and have them feel the difference in their hands and their body.  As the patient gets comfortable you can cue the patient to breath in through the nose and out through the mouth, exhale longer than the inhale, and try to expire all of their air.http://www.youtube.com/watch?v=IfZRnFD5m_QOther biomechanical interventions can be separated into mobility and stability categories.  Part I focused on the stability aspect of the inspiration, but it can also be used for mobility (yoga has been doing this for thousands of years).

Mobility

Much like ligament locking for joint mobilization/manipulation, the breath can be directed by altering postures and positions.  Leslie Kaminoff describes breathing as the act of "shape changing".  Using this theory you can alter your posture to direct the where the breath ("shape change") occurs.  It's physics.  The shape change from inspiration (expansion) will always go towards the place of least resistance.For example, if a patient has a restricted R posterior lumber quadrant, then you would put them in a childs pose reaching contralaterally with their R UE.  Since you closed off the L side by laterally sidebending/flexing and closed off the anterior R rib cage by flexing, the only place for the shape change to occur would be into the R posterior quadrant.  You can further increase the expansion (stretch) into this area using tactile or verbal cues to get them to breath into the postero-lateral R rib cage.Another mobility aspect of breathing is it's amplification of the parasympathetic NS.  This can be very advantageous when performing manual techniques or corrective exercises to increase tissue extensibility.  Muscle guarding and reflexive activation can be minimized by focusing on breathing.

Stability

As mentioned before with the high-threshold strategies, simply having your patient breath properly during exercises will help establish proper inner core stabilization.  One important consideration is that you must simultaneously monitor their posture.  You always want a neutral spine.  Performing a task with an anterior pelvic tilt not only causes compensatory mechanisms, but it prevents proper breathing mechanics (decreased ZOA, decreased eccentric abdominal & PF contraction).Again, the guy with a positive scour sign, hip impingement, and anterior pelvic tilt doesn't want to hear about breathing.  He just wants his hip to stop hurting so he can get back to golfing.  So instead of going into too much detail about the mechanics of breathing or working on isolated breathing exercises, simply have your patient breath with a neutral spine during all their exercises.  It's a great place to start and ensures that the patient is performing the exercise with the correct musculature.Since I have learned about the importance of breathing I no longer time my patients with a stopwatch.  I now have everyone counting their breaths (i.e. holding quadruped diagonals for 7 breathes instead of 30 sec).For advanced patients you can progress to "breathing behind the shield".  This is a term coined by the great Pavel Tsatouline.  It's a great way to incorporate breathing with core stability.  It describes the act of maintaining abdominal tension while breathing.  "Breathing behind the shield" is the balance of controlling intra-abdominal pressure and abdominal & pelvic floor muscle tone.  It displays that the patient is able to use the diaphragm's dual function: respiration and stabilization.Hans Lindgren has an amazing video on assessing and interventions for breathing and core stability.  At about 2:10 into the video he goes over a great technique to help you teach your patients how to "breath behind the shield".  This is a great place to begin and can be progressed through the developmental sequence.

Bottom Line

There are many ways to assess and treat dysfunctional breathing patterns.  Hopefully this article will give you a good place to start.  Below are some great articles, videos, and descriptions of breathing patterns.  As with every intervention, it is important to master this yourself before you try to teach your patient.

Dig Deeper

Dean SomersetHans Lingren - Core Stability Inside OutRosalba CourtneyErson ReligiosoSportsRehabExpert - Ron Hruska InterviewMike Robertson - Video Coaching - Stress & BreathingPatrick WardPostural Restoration InstitueConnor CollinsCraig LibensonBill HartmanTara RobertsonCraig LiebensonSimple Exercise - Crocodile Breathing

References

Tom Myers & Leslie Kaminoff.  The Breath in the Pelvis - Seminar (NYC 2012).Courtney R,Reece J (2009). Comparison of the Manual Assessment of Respiratory Motion (MARM) and the Hi Lo breathing assessment determining a simulated breathing pattern.  International Journal of Osteopathic Medicine.Courtney R (2009). The functions of breathing and its dysfunctions and their relationship to breathing therapy.  International Journal of Osteopathic MedicineCourtney R (2011).  Dysfunctional Breathing - It's paramaters, measurement and relevance.  Thesis RMIT University. (a must read - click here)Kaminoff L. (2006). "What yoga therapists should know about the anatomy of breathing." International Journal of Yoga Therapy.McLaughlin L. (2009). "Breathing evaluation and retraining in manual therapy." Journal of Bodywork and Movement Therapies.McGill S , Sharratt M ,Sequin J P. (1995). "Loads on spinal tissues during simultaneous lifting and ventilatory challenge." Ergononomics.Janssens L , Brumagne S, Polspoel K, Toosters T, McConnell A. (2010). "The effect of inspiratory muscles fatigue on postural control in people with and without recurrent low back pain." Spine.Hodges P , Heijnen I, Gandevia S C. (2001). "Postural activity of the diaphragm is reduced in humans when respiratory demand increases." Journal of Physiology.Hodges P , Butler J ,Mackenzie D K, Gandevia S C. (1997). "Contraction of the human diaphragm during rapid postural adjustments." Journal of Physiology 505(Pt. 2Wang S., McGill S (2008).  Links Between the Mechanics of Ventilation and Spine Stability.  Journal of Applied Biomechanics.McGill S, Sharratt M & Seguin J (1995). Loads on the spinal tissues during simultaneous lifting and ventilatory challenge. Ergonomics.Robey J, Boyle K (2009). Bilateral Functional Thoracic Outlet Syndrome in a College Football Player. N Am J Sports Phys Ther.Boyle K, Olinick J, & Lewis C (2010).  The value of blowing up a balloon.  N Am J Sports Phys Ther.Kolar P, Sulc J, Kyncl M, et al. (2010) Stabilizing function of the diaphragm: dynamic MRI and synchronized spirometric assessment. J Appl Physiol.Kolar P, Sulc J, Kyncl M, et al. (2012).  Postural Function of the Diaphragm in Persons With and Without Chronic Low Back Pain. JOSPT.Hagins M, Lamberg EM (2011). Individuals with low back pain breathe differently than healthy in- dividuals during a lifting task. JOSPT.Clifton-Stmith T, Rowley J (2011). Breathing pattern disorders and physiotherapy: inspiration for our profession.  Physical Therapy Review.Hruska R (2005).  ZOA Position & Mechanical Function.  Postural Restoration Institue.Cook, Gray. Movement: Functional Movement Systems : Screening, Assessment, and Corrective Strategies. Aptos, CA: On Target Publications, 2010. --The main reason I do this blog is to share knowledge and to help people become better clinicians/coaches. I want our profession to grow and for our patients to have better outcomes. Regardless of your specific title (PT, Chiro, Trainer, Coach, etc.), we all have the same goal of trying to empower people to fix their problems through movement. I hope the content of this website helps you in doing so.If you enjoyed it and found it helpful, please share it with your peers. And if you are feeling generous, please make a donation to help me run this website. Any amount you can afford is greatly appreciated.

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