toronto

Running Strong: Video Analysis, Running Re-education and Strength and Power Program for Runners

The Running

Strong Program

What is it?

A 4 session program to improve your running and decrease your chance of injury.

What is it composed of?

  • Detailed analysis of your running history and programming to find predictors of injury
  • High Speed Camera (240 frames/second) analysis of your running form
  • Pelvic Drop
  • Detailed functional evaluation of your physical function designed to find weak links
  • Custom created corrective exercise and performance based exercise program including 3 follow up sessions

Is it covered by insurance?

 

Yes.  I am both a physiotherapist and chiropractor.  Each session can be billed separately and our rates are well within the normal fees charged for regular physiotherapy sessions

The cost?

$400.00 for the initial 1 hour session plus 3 follow up sessions.

The timeframe?

The timeframe is surprisingly flexible.  Some people need a follow up session within a week of the initial evaluation.  Others might need a follow-up session within 3 weeks.  Having this flexible time frame allows us to tailor the program to your needs.

Can I work with my existing coach or personal trainer?

Absolutely.  In fact, this is encouraged.  I regularly work with running or triathlon coaches to create safer and better training programs.  If you already work with a personal trainer we can speak with your trainer about encorporating the running performance program into your existing exercise sessions.

About Me:

I am physiotherapist and chiropractor with a MSc in Exercise/Spine Biomechanics.  I have published more than 20 peer-reviewed academic papers on exercise science and injury.  I regular work with runners and multisport athletes from beginner's to Olympic athletes.  I currently write injury prevention articles for Triathlon Canada.  I am also an instructor with therunningclinic.ca - Canada's, if not the World's, leading course on the prevention and treatment of running injuries.  Last, I am the clinical director of Medcan's Run Well 3D Kinematic Analysis Program for Running Injuries.

Related Posts

1. Running Strength: Moving beyond the Core

2. Running Biomechanics: Clinical decision making in running analyses

3. Gait Modifications for Runners.

 

Clinical decision making in running form interventions: implications for injury

hip-adduction-and-knee-abduction.jpg

Clinical Decision Making in Running Form Interventions Initially written for Medbridge Education

The purpose of this article is to highlight the clinical decision making process during kinematic running analyses - focusing on evaluating the kinematic risk factors for running injury and not kinetics.

Both predictive and correlational research attempts to identify kinematic variables that are associated with an individual’s future or current injury.  Many of those being:

-higher levels of pronation or pronation velocity

-abductor twist

-increased tibial internal rotation

-increased knee abduction

-increased hip abduction or hip internal rotation

-pelvic drop

-stride rate

All of the above variables have been either documented as being elevated in runners with injury (correlated) or have been found to be precede the onset of injury (longitudinal research).  As with most human function nothing is that straightforward though.  To confuse us, all of the above factors have also been shown to have NO relationship to injury in other studies.  We now have this dueling evidence base where it is very easy to cherry pick research supporting our ideas.

Pain and injury are multifactorial – simply suggesting that an injury is due to altered kinematics ignores the wealth of research highlighting the many variables that influence the pain experience. Thus, our clinical decision making is never as simple as finding a “flaw” and assuming that that is the driver of the injury.  So how can we view these “flaws”?

Kinematic flaws and how we interpret them can be divided into three categories:

  1. Defect: the kinematic flaw is a deficit in function leading to a future injury or pain
  2. Defense: the kinematic flaw is not a flaw but is only correlated with the injury.  The altered movement itself may be driven by nociception and is a consequence of the injury or pain.  The kinematics may be driven by protective motor output
  3. Red herring: the flaw is not a flaw but merely an expression of the large amount of functional variability that exists across people.  The flaw preceded the injury and will remain even with changes in pain.

Injury is the failure to adapt stress

To determine the significance of a kinematic flaw a few assumptions regarding the nature of injury and pain are necessary. These are naturally open to debate.  First, injury and pain should not be conflated.  Runner’s can have tissue anomalies that many might view as pain (e.g knee OA, hip labral tears) and have no pain.  They can also have pain with no evidence of disruption in connective tissue.  Pain can be viewed as the brain’s response to the perception of a threat. With many factors (cognitions, past experiences, expectations, emotions) influencing the brain’s decision to output pain – nociception created by mechanical deformation of nervous tissue being just one.

With runner’s all of these factors can be viewed as stressors inputted into the system.  An ideally adapting system (at least for those who want to run pain free) would be one where the brain does not output pain.  Pain occurs when some immeasurable threshold is reached where the brain perceives a sufficient enough threat to output pain.  An injury can be viewed as the body’s failure to adapt to the imposed loads that exceed the threshold for positive tissue adaptability.  It is assumed that both the body and brain have the ability to positively adapt to imposed demands or loads. It assumes with appropriate and graded loading that both our connective tissue strength and our pain thresholds can be improved.  Injury-free and pain-free running require us to stay below these thresholds.

How kinematics might contribute to pain

Altered kinematics may either create an initial noxious event leading to nociception, may contribute to nociception by continuing to sensitize nervous tissue or may even indicate a movement habit that a runner has fallen into and nociception itself does not need to be present.  This habit of movement may even, to quote Lorimer Moseley, “facilitate protective neurotags”.  What might initially have been a movement flaw that helped the system (e.g a defense) has now become associated with pain that has no further value.  Our conundrum as clinicians is not determining whether the altered kinematic is cause or consequence of pain but rather determining if there is value in trying to address it.

Is this a flaw?
Is this a flaw?

How and when to address Kinematic Flaws

After we perform a running analysis we might find a number of kinematic variables that might be related to injury.  The flaws we see pose two questions:

  1. Can the kinematic flaw be reasonably linked to the runner’s pain or injury?

Going back to the assumption that injury or pain may occur when the demands on the body exceed its ability to adapt can we suggest that the kinematics measured might load the area of injury to such an extent that mechanical pain would occur?  If a patient presents with medial leg pain, appears to pronate a great deal and the speed of that pronation appears elevated we might be able to suggest that those variables relate to the pain as biomechanical link of increased tissue strain can be made.  This idea can be bolstered with post-hoc reasoning if simple interventions that might address the flaw (e.g taping an arch, running with a wider step width) positively change the pain experience.  This thinking would be bolstered by some research that supports this link.  But wait you naturally scream at me, there is lot of research suggesting pronation has no relevance to injury.  This is absolutely true and leads us to a second question.

  1. What factors can mitigate or amplify the relevance of this flaw?

Rather than increased pronation and increased pronation velocity being interpreted as a defect we might argue it is merely a red herring.  We see this in a number of elite runners with massive amounts of pronation and massive amounts of mileage and speed.  Yet they have no pain.  What factors might mitigate the proposed risk of having this assumed kinematic flaw?  Could those with what appears to be a running kinematic flaw have adapted to this ‘flaw” over time?  Have they progressed their mileage slowly over years?  In some instances, flaws aren’t flaws.  The runner is fully adapted to that gait style.

On the other hand, a novice runner may exhibit running mechanics sometimes associated with injury.  She may be able to run pain free for awhile until suddenly pain develops with no change in her training.  There has been no change in the loading placed on nervous tissue yet pain is experienced.  A possibility exists here that the sensitivity of her system was changed.  Thus her threshold for pain or injury was decreased.  Since multiple factors influence this sensitivity it is important to attempt to address those factors.  One such intervention would be to address the mechanics of her gait.

Strategies to address Kinematic Flaws and Pain

What’s great with treating running injuries is that we don’t always need to change the kinematic flaw.  We have a number of studies showing that gait retraining can change both pain and running kinematics but we also have research suggesting that interventions can result in changes in pain with no changes in kinematics. In the latter instance, we can use the altered kinematics as a starting point in creating our therapeutic interaction.

At it’s most basic, treatment is merely the modification and judicious application of stress.  The following two-step and not mutually exclusive approach can be used:

  1. Desensitize and Unload
  2. Increase tolerance to stress

Desensitize and Unload

Much of what a manual therapist does would fit into this category.  Again a multifactorial approach may be necessary.  Interventions may be pain physiology education, education about tissue and nervous system adaptability, taping, temporary orthotic use, gait retraining, manual therapy, movement therapies and alterations in training loads.

Increase tolerance to stress

I believe most runners can keep running.  In fact, they need this stressor to adapt.  If we teach runners the importance of the adaptability of their system then they will understand the importance of a graded return to activity. Gait retraining would also fall into this category but it should be remember that gait modifications primarily redistribute forces during running.  Thus a slow return to running with a new style is advised to again allow for the adaptation to the different stress.  Last, we can use kinematics as a window into prescribing capacity or motor control exercises.  Resistance training can be justified in running injury treatment both as a pain modulator and under the idea that a tissue’s response to loading can be improved – increasing injury threshold.

A future post will elaborate on the clinical decision making of these interventions. A helpful course on understanding running biomechanics and injury can be seen in this link.

Summary

We don’t know the ideal way to run and by extension we don’t know what are true kinematic flaws in running.  We know that pain and injury are multifactorial and taking this big picture view of rehabilitation is helpful.  Identifying what may be kinematic flaws can still provide a window into interacting with a patient.  Addressing kinematic flaws, along with a runner’s clinical presentation, through a multimodal approach (e.g. desensitization, education, gait retraining, exercise selection, activity modification) is a comprehensive approach that recognizes clinical uncertainty.

Case Study: Unexplained dead leg when running. Altered nerve tension?

Purpose: Demonstrate a case of an altered nerve tension in a runner that may be exacerbated by their running technique. Case Details

Female, late twenties, competitive runner (sub 20 minute 5km, 1:30 half marathon, 3:15 full marathon)

Symptoms

- 2 year history of left lateral lower leg pain that comes on with running

- begins around 20-30 minutes into a run and often feels like she can't control her leg with a sense of numbness (like she might fall)

- but no obvious swelling, shininess or pain in the anterior compartment during these bouts

Select Physical Exam Findings

- neuro screen, strength, ROM, single leg squatting, usual "functional tests" are all normal

- no significant pain on palpation of entire lower leg

- positive Slump test with a bias toward the superficial peroneal nerve.  This also occurs during a straight leg raise test with a superficial peroneal nerve bias.  The sensation felt is the same as that felt during running.  The video below is essentially the test movement (except change the ankle dorsiflexion for plantar flexion/inversion)

http://youtu.be/Xy1Lv3FK2Dk

Running Analysis

In the video below I noticed two things that may be significant.  This runner is predominantly a forefoot striker even at slow speeds.  Quite rare.  She essentially reaches out for the ground with her forefoot.  If you notice her knee it is actually quite extended just before foot strike.  This is not normal. See a kinematic review of running here. There is usually quite a bit of knee bend before landing and of course on impact.  Simply, this runner overstrides with a forefoot strike. She does this both in shoes and in socks.  This position is similar to the Straight Leg Raise test with a peroneal nerve bias and it may be contributing to the "funny" feeling in the leg.  A review of running biomechanics with video can be seen here.

http://youtu.be/h7W7cWYhCDw

Differentials

I can't rule out exertional compartment syndrome but I also can't confirm that with ease as the test would take over 3 months to get here in Toronto.  And Andy Franklyn-Miller (UK sports doc with a great deal of experience studying this type of thing -  website here) would suggest that this test is even questionable for this condition and we might even want to question the condition itself.  So I keep the exertional compartment idea in my head and look at other possibilities.

Why I question the compartment syndrome is the positive response I get when I stress the superficial  peroneal nerve with neurodynamic testing.  I don't believe that this is a classic response for exertional compartment syndrome suggesting to me that we have an altered neurodynamic on our hands.

Treatment

- explain pain, always explain pain

- at home - every hour, 5-6 nerve sliders for the peroneal nerve (video below but don't dorsiflex the foot)

http://youtu.be/y-cXei4e_wM

- running changes: this is tough but our runner is working on a midfoot strike and is trying to cue the idea of landing behind her (this is impossible but it can get the idea across).

- I also treat the "container" of the nerve.  I do gentle soft tissue work (I used to be an  A.R.T guy but I am much gentler now and don't believe the theory they propose) along the entire sciatic nerve. I think that I am really the nervous system and ultimately influence the muscle and the peripheral nerves with my manual therapy.  You can explain this treatment anyway you like. I choose a neural based explanation rather than thinking that I am digging out adhesions.

- I believe runners should be strong.  And not just runner strong - athlete strong. This runner has had previous high hamstring tendinopathy/tearing (or possibly sciatic nerve or all the little nerves back there irritation) so she is on a heavy resistance training program for everything.  I don't emphasize anything - I just train for balance, capacity and variety.  She gets exercises like one leg deadlifts, deadlifts, squats with bands, hip thrusts, hip airplanes, bridges, clamshells, one leg squats, one leg lateral wall squats, nordic hamstrings, push ups, suitcase carries etc.  Click here for a "hamstring" injury for runners sample program for videos

Is she better?

Sorry, don't know yet.  Just started.  Any ideas please let me know.  I can say that after I gently treat the region around the sciatic, tibial, peroneal nerve we are able to decrease the sensitivity associated with the SLR testing. This is a good sign. I am cautiously optimistic.

Barefoot, forefoot strike and heel strike - a biomechanics summary

Audience: Runners and therapistsPurpose: To summarize the biomechanics of running strike pattern and shod conditions

I feel like in the blogosphere and the popular running media that there is a love affair with all things barefoot.  Barefoot running is associated with forefoot striking and there appears to be changes in the biomechanics associated with alteration in running form when compared with heel striking.  However, the research gets presented as if it is very neat in tidy when in fact it is quite murky.  This post is a work in progress.  It attempts to summarize some of the work comparing barefoot running with shod running and the work that compares forefoot striking and rearfoot striking while running in shoes.  I hope that I have conveyed that the results are quite conflicting.  Hence, what a pain it was to try to summarize this work.

This post will be updated consistently. Please view it as a work in progress.

A. Changes when going from shod to barefoot running

Kinematic changes

-there is a trend to shift  from rearfoot striking to landing more on the midfoot or forefoot

-an increase in step frequency (e.g. more steps per minute)

-a decrease in step length (Divert et al 2008, Squadrone 2009)

-the foot is more plantar flexed (i.e. the toes point down at contact) and there is a greater degree of ankle motion (Pohl and Buckley 2007, Lieberman et al 2010)

-a decrease in the amount of peak pronation or calcaneal eversion (Morley et al 2010) which is most evident in runners who pronate a great deal.  Going barefoot decreases peak eversion from 10.3 degrees to 6.7 degrees in moderate pronators and from 14.8 degrees to 9.2 degrees in super pronators.

-the time it takes to get to maximal calcaneal eversion decreases in barefoot

-total eversion distance is increased with barefoot running.  Even though there is less pronation the foot starts in a greater degree of inversion when barefoot.  Therefore, the heel travels a greater distance when striking the ground to reach maximal eversion/pronation.

Force or Impact changes

-a decrease or complete reduction in the impact peak (aka. impact transient) when the foot strikes the ground but the push off peak is unchanged. A shod heel strike vertical ground reaction force can be seen in this video from Dr. Lieberman:

http://www.youtube.com/watch?v=zavoQM3727s&feature=player_embedded

In the following graph notice how the first "bump" is lower in the barefoot and forefoot condition when compared with the rear foot shod condition (Divert 2008).

Ummm, is the initial impact transient eliminated with Barefoot running?

The initial impact transient is not always eliminated with barefoot running. While, other researchers (Lieberman 2010) show that the initial impact peak or impact transient is completely washed out rather than just decreased this is not always seen. Dr Lieberman's work is fantastic and his argument is beautifully laid out.  His website is here (http://www.barefootrunning.fas.harvard.edu/4BiomechanicsofFootStrike.html)

He also provides this video showing the impact transient loss when running barefoot and forefoot striking.

http://www.youtube.com/watch?v=TjrEyfQC5NQ&feature=player_embedded

In the study by Divert (2008)  three out of the 12 subjects continued to demonstrate an impact transient. This difference may be due to the fact that other studies investigate youths who have always run barefoot while in the above graph (from Divert 2008)  the subjects were just learning to run barefoot and may have not run a sufficient number of steps for the body to adapt and modify its kinematics.   In effect, the sample used in the above study may have  not had enough time to learn how to run barefoot to eliminate that impact peak.

Nonetheless, below is a graphic by Dr. Lieberman showing the loss of the impact transient with barefoot forefoot striking

In contrast to Dr. Lieberman's work, other studies have also looked at habitually barefoot runners and have NOT found a complete loss of the impact peak, albeit a reduction was found when running barefoot or in Vibrams versus a standard shoe. Squadrone (2009) compared barefoot, shod and Vibram wearing runners in athletes who have had extensive experience running barefoot (3 of them having completed a marathon barefoot).  In the following graph notice how the impact transient is still greatest with shoes, decreases with barefoot and is most modified with Vibrams (VF).  Most importantly, notice how the impact transient still exists.  These authors did not calculate the slope of this impact transient so it can not be directly compared with the work of Lieberman et al (2010).

How can this impact transient still exist in minimalist or barefoot runners?

One difference between Lieberman's group and Squadrone's group may be the degree of plantar flexion in the ankle that occurs at footstrike in both groups.  In Squadrone's group the ankle is at 94 degrees - this means about 4 degrees of plantar flexion.  In Lieberman's group the plantar flexion in habitually barefoot Kenyan youths is around 14 degrees.

This is an important point which leads to a main thesis of this article.  It implies that barefoot or minimalist running alone is NOT A SUFFICIENT condition to obliterate your impact transient during foot strike.  In fact, if you run barefoot in a heel to toe fashion you will see an increase in the impact transient.  This was seen in the work by De Clercq (2000) who compared barefoot versus shod but made everybody still run with a heel strike.  This was found a decade later by Dr Lieberman.  De Clerq found this:

Not to be too confusing but the above authors also measured foot dorsiflexion at impact and found an ankle angle of around 94 degrees (4 degrees of plantarflexion) with a sole angle around 12 degrees (I believe the sole angle is the angle of the entire foot relative to the flat ground).  Zero degrees would be flat while 12 degrees means the toes are pointing up relative to the ground (this is my interpretation, it was not explained in the article). This ankle angle in the barefoot condition is similar to the Squadrone's study of 94 degrees yet we see an impact transient as well as a greater rate of force development in the barefoot condition.  My interpretation here is that while the ankle was slightly plantarflexed the heel still came down first (i.e. the sole angle was still pointing up).  I don't know what the sole angle was in the Squadrone study but it  certainly might help explain the difference between studies.

Bottom line about barefoot.

Obviously barefoot running is no panacea for eliminating an impact transient.  Additionally, there are other factors associated with barefoot running (e.g Kinematic variables: stride rate, stride length, ankle range of dorsiflexion, range of pronation) that may influence many of the kinetic variables (e.g. impact transient, ground reaction forces).  And most importantly how does it relate to injury and performance?

So lets look at these other variables.  Very simply, barefoot running seems to shift someone from being a Heel striker to being a forefoot striker.  A small amount of research has investigated the differences while running in shoes with a rearfoot versus a forefoot strike pattern.

Can changing your foot position at foot strike influence Kinematics and Kinetics?

They sure can, please read more.  Dr Irene Davis has been involved in much of this research but there is surprisingly little published.  Dr. Davis' published work often cites her unpublished lab findings when comparing a Rearfoot strike (RFS) with a forefoot strike (FFS).  Some of what I cite below will refer to Dr. Davis' statements (Williams et al 2000 or Laughton et al 2003)  in her introduction or discussion instead of her actual data (which I can not get a hold of).

Kinematic and Kinetic Changes when moving from a rearfoot to forefoot strike

Kinematics

- forefoot strikers have increased calcaneal eversion excursions and eversion velocity (McClay and Manal 1995a/b) but end up with less maximal calcaneal eversion (aka pronation)

- the foot lands with greater ankle plantar flexion and is in greater inversion at foot strike in the Forefoot strike condition.

--increased knee internal rotation velocity in Forefoot strike conditions (Williams et al 2000)

Changes in Leg Stiffness

-According to the work of Laughton et al (2003) forefoot strikers have greater leg stiffness in general but less ankle stiffness.  They have less ankle stiffness because there is more time and range of motion for the ankle to bend. Essentially, there is more time for the ankle to spread out the joint torque during impact because the ankle moves a through a larger range with the forefoot strike (remember, the foot contacts the ground with the toes down in plantar flexion) (Laughton et al 2003).  These authors also found that the knee does not flex as much in the forefoot strike condition as in the rearfoot strike conditions (30 degrees versus about 34 degrees) therefore there is greater overall leg stiffness.

-Conversely, according to the work of Lieberman et al (2010) forefoot strikers have greater leg compliance (defined as the drop in the body’s centre of mass relative to the vertical force during the period of impact) meaning there is also greater Knee flexion as well as ankle flexion when striking with the forefoot.

Inconsistent changes in Impact Force with forefoot strike

Dr Lieberman's website has an excellent video that shows modifications in the impact transient when striking with a forefoot in shoes.  Unfortunately, this kinetic information is not accompanied with a great deal of kinematic information.

Dr Lieberman has shown the loss of the impact transient in the following video:

http://www.youtube.com/watch?v=XO4MruQov4Q&feature=player_embedded

However despite this decrease in the impact transient documented in the video  the one other study that investigated Shod running and changes in foot strike pattern show different results.

A review of Laughton et al (2003)

These authors compared rearfoot and forefoot strikers ground reaction forces and found the following:

-There is less peak tibial positive acceleration in the rearfoot strike condition

-The average peak vertical ground reaction force, the anteroposterior peak GRF (i.e. the braking force),and average anteroposterior GRF load rates were significantly greater for the FFS pattern than for the RFS pattern

-Average and instantaneous vertical GRF load rate (i.e. the impact transient), however, did not differ significantly between the FFS and RFS patterns.

-BUT...in the Laughton study the forefoot striking runners were different than your typical forefoot strikers.  You might actually call the TOE runners because when their forefoot struck the ground they were not allowed to let their heel strike the ground.  This is not what happens with barefoot/forefoot running.  This may account for the differences in loading.

Is this getting CONFUSING?

What I take from this is that forefoot striking can certainly decrease the loading rates on the foot/shank to a similar extent as barefoot running.  But again, it is not a SUFFICIENT condition.  I would guess that it might even be possible to train yourself to run with a heelstrike but in such a manner that you decrease your impact transient.  Work out of Dr. Davis' lab that gives feedback to individuals on their tibial shock shoes that people can learn to run softer and decrease the impact transient. In these studies (click here) no advice is given to forefoot strike and individuals wear neutral shoes.  They are merely asked to run softer and are given feedback.

I don't have a definitive answer for why the Laughton study shows no change in the impact transient yet Lieberman's work shows a significant decrease in the loss of the impact transient.  My hunch is that other kinematic variables may influence the loading through the foot.   One explanation may be that if in the Laughton study there was no difference in the stride length when shifting to a forefoot strike from heel strike then this may account for the lack of a loss of the impact transient (couple this with the lack of the heel being allowed to lower to the ground - a type of impact absorption and this may explain our differences).

What is missing in this review

- research investigating whether individuals could wear standard running shoes yet still be trained to run in a manner that mimics all of the kinematics of barefoot, forefoot strike running.

-any research investigating the theory (I stress theory) that running in shoes influences plantar foot proprioception which in turn negatively influences running - this belief is very common and is always written about in a superficial  manner.  Yet there is not a lot of research investigating it.  I will reserve an opinion.

-a full body kinetic analysis comparing all the different foot conditions of running.

-long term studies investigating changing stride mechanics on injury prevalence and running efficiency

-I purposefully left out the good research investigating the POSE technique

Clinical Relevance - What I tell my patients

I think it is too early to give barefoot running the gold medal and switch everyone to minimalist shoes but I am certainly open to the idea.  Runners were still getting injured with minimalist shoes in the 1970s (see a pdf review here: Am J Sports Med-1978-James-40-50 running injury overview from 1978 surprisingly good we know nothing new)

Barefoot or forefoot strike running may be an excellent adjunct to the recreational runner as a training stimulus.  It can be used as a form of strength training or rehabilitation.

No research has looked at the impact transients with runners who run much slower than what is studied in these papers.  Most of these papers have the slowest runners running 5 minute kilometres (an 8 minute mile).  The vast majority of your recreational runners do not run this pace.  If you run at 25 minute 5 km you will probably be in the top 10% of a large race (for example, at the 2010 Goodlife Marathon 5 km a 25 minute result put you 178th out of 2721) and the top 15% if you keep that pace up for a marathon.  So, do we want to be telling all our runners to covert to a forefoot strike, minimalist shoe or barefoot based on the research of relative elites? the only correct :) answer is -----I have no idea.

Good luck piecing this all together and stay tuned for more updates.

Greg Lehman

Toronto Physiotherapist

References

Squadrone R, Gallozzi C. Biomechanical and physiological comparison of barefoot and two shod conditions in experienced barefoot runners. J Sports Med Phys Fitness. 2009 Mar;49(1):6-13.

Divert C, Mornieux G, Freychat P, Baly L, Mayer F, Belli A. Barefoot-shod running differences: shoe or mass effect? Int J Sports Med. 2008 Jun;29(6):512-8. Epub 2007 Nov 16.

Pohl MB, Buckley JG.Changes in foot and shank coupling due to alterations in foot strike pattern during running.Clin Biomech (Bristol, Avon). 2008 Mar;23(3):334-41. Epub 2007 Nov 19.

Morley JB, Decker LM, Dierks T, Blanke D, French JA, Stergiou N. Effects of varying amounts of pronation on the mediolateral ground reaction forces during barefoot versus shod running. J Appl Biomech. 2010 May;26(2):205-14.

Lieberman DE, Venkadesan M, Werbel WA, Daoud AI, D'Andrea S, Davis IS, Mang'eni RO, Pitsiladis Y.Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature. 2010 Jan 28;463(7280):531-5.

Carrie A. Laughton1, Irene McClay Davis2, and Joseph Hamill Effect of Strike Pattern and Orthotic Intervention on Tibial Shock During Running JOURNAL OF APPLIED BIOMECHANICS, 2003, 19, 153-168

Williams DS, McClay IS & Manal K: Lower extremity mechanics in runners with converted forefoot strike pattern. Journal of Applied Biomechanics, 16(2): 210-218, 2000.

McClay, I., & Manal, K. (1995a). Lower extremity kinematic comparisons between forefootand rearfoot strikers. In K.R. Williams (Ed.), Conference Proceedings: 19t Annual Meeting of the ASB, Stanford, CA (pp. 211-212). Davis, CA: UC–Davis.

McClay, I., & Manal, K. (1995b). Lower extremity kinetic comparisons between forefootand rearfoot strikers. In K.R. Williams (Ed.), Conference Proceedings: 19th Annual Meeting of the ASB, Stanford, CA (pp. 213-214). Davis, CA: UC–Davis.

Neuromuscular knee control exercise series

Audience:  Patients Format:  Patient Handouts

Topic:  Trunk, hip and knee motor control exercises to improve control of knee position

This post is  a handout that I give to patients.  As with all exercises they should be done under some supervision (physiotherapist, personal trainer, chiropractor) and always with a health professionals guidance.  In no way are these exercises stand alone.  They should be tailored to each patient's needs and progressed or modified accordingly.

Gregthebodymechanic poser neuromuscular retraining for hip stability

The Side Bridge: The best exercise. ever.

Intended Audience:  anyone who has not already been doing this for years

OK, OK.  There is not just one perfect exercise for everyone.  But this one comes close and for reasons you don’t expect.  The side bridge is an exercise that is typically thrown into the category of the “core” and people think it is just done as a replacement for oblique ab crunches.  While yes, it is a great replacement for that exercise it provides so much more.

The power of the side bridge extends beyond your obliques.  The sidebridge influences every muscle that the obliques touch or are related to.  Here are some quick facts about the side bridge exercise:

  • It works your upper and lower back muscles more than 40% of their maximum.  This is more than many common back exercises
  • Not only does it work your obliques exceptionally well (about 50% of their maximum) it works your rectus abdominis (the sixpack muscle) very well (about 34% of its maximum).  This is about the same as doing a crunch or front bridge exercise.
  • The sidebridge is and excellent exercise to train a deep back muscle called the Quadratus Lumborum.  The QL is an important muscle for providing stability to your spine
  • The sidebridge is one of the best ways to work your hip abductor muscles.  The hip abductor muscles work at about 74% of their maximum during the side bridge.  This is almost double the work that this muscle does during the exercise that is most commonly prescribed for hip muscle weakness, the side lying leg raise.

Modifying the sidebridge

You can do the regular old side bridge or you can change things to make it easier or harder.

  • Lift your top leg up.  This increases the stress on the side of the body closest to the ground.
  • Flex at the hip of the bottom leg.  This puts all of the weight on your top leg and is excellent way to train your inner thighs (e.g. your hip adductor muscles).  This should be an exercise for all Hockey Players
  • Instead of supporting yourself from your forearms or feet you can support yourself from your knees (easier) or from you hand (easier on the muscles but harder to balance)

Why is all this important?

If you are a runner, triathlete, cyclist or swimmer than the sidebridge could be part of your conditioning program.  Ideally, the sidebridge is done at a minimum of three times per week.  The bridge position can be held for 3-10 seconds and then you can “roll” to the other side, hold that position and then roll back.  Keep repeating this until you can’t hold your form.  Rest two minutes and do it again.

The simplest rationale for the sidebridge is that it builds your muscles capacity to provide hip and trunk stability/stiffness.  The muscles stressed help keep your pelvis level and your spine in a strong position.  This might be important to prevent back and hip pain (the jury is out) and might help prevent or treat  knee injuries.  A potentially  important aspect of knee pain is hip movement/stiffness and hip abductor weakness.  The sidebridge is ideal for improving hip strength which might increase performance or decrease injury risk. 

Jewels from Juker (1998). Insight into the Psoas Part One

Stu McGill was an author on this paper when it came out back in 1998.  At the time, I was one of Stu’s grad students putting electrodes onto anyone I could find for the price of Gyro sandwich.  I even burned (chemically and transiently) the thigh of a girlfriend at the time.  I knew how to treat the ladies.  Unfortunately, I never really picked Stu’s brain about this paper.  It was only relevant to me at the time because we were strongly questioning the necessity of double leg lifts as an exercise for the "lower abs".  We felt they were unnecessary to recruit the lower abs and too costly because of the compressive and anterior shear component applied to the lumbar spine. Our argument was that there is no difference between the upper section of the rectus abdominis and the lower section.  I still stand by it and the paper is here ( http://ptjournal.apta.org/content/81/5/1096.full ). Regardless of my youthful oversight, I still love the paper and the ideas of sticking needles into the psoas.  It must feel awesome hence the “n” of only 5. Below are a few tidbits that will lead into future posts on psoas function. 1. the psoas was only minimally active (less than 5% of maximum) during a squat lift and while lifting 40 kg pails in both hands.  This suggests that during these tasks the psoas has a very negligible role for both stability demands and creating the primary movement.  This finding certainly questions the psoas importance as a stabilizer of the lumbar spine.  Although, part of Paul Hodges' research cabal recently put out a good paper (as usual) that showed that the psoas fired bilaterally (the only hip flexor muscle to do so) during an Active Straight Leg Raise (one leg only).  Again, suggesting its importance for stability.

2. the psoas was most active while standing with the hip flexed 90 degrees while a maximal force is applied against the knee in an attempt to extend the hip.  The psoas reached 100% max activity.  When the same action occurs while lying on ones back the average activity drops to approximately 57%.  This is cool although certainly not revolutionary to most.  It suggests that the psoas is not only working to flex the hip but to keep pelvis level – the psoas is working to create an ipsilateral lateral bending moment about the lumbar spine to help the contralateral hip abductors and probably the ipsilateral QL.

3.The limits of reciprocal innervation.  It is commonly stated that to inhibit one muscle we must activate its antagonist, aka. Sherrington’s law of reciprocal innervation.  In my opinion this is a pretty overused “law” in the Kinesiology field.  It is thrown around to justify treatments or explain dysfunction with really minimal if any research support.  The Juker paper took a look a the notion that the psoas could be inhibited during the sit up if the  hamstrings (a psoas antagonist) were activated. This hypothesis was not supported by Juker’s results, and in fact psoas activity was increased (28 % and 34 % MVC for the press heels style of situp) compared with that during bent knee sit-ups (17% and 28% MVC)

Big mouth comment:  Does the “law” of reciprocal innervation only apply when it is expedient.  We use it to justify PNF stretching, the “active” component of ART and to explain that a “tight or spasming” muscle is constantly inhibiting another muscle.  Yet, we ignore this law’s power during common activities.  Co-contraction of both agonists and antagonists is fundamental to stability and many movements (e.g. both the hamstrings and quadriceps fire simultaneously during running or squating – Lombard’s paradox. See link http://en.wikipedia.org/wiki/Lombard%27s_Paradox).  I would really like to know what a real neurophysiologist says about this. I have always been  under the impression that reciprocal innervation/inhibition functioned at a reflexive level rather than at the voluntary activation level.

Part Two of this post will look at other “old” research that investigates Psoas function with questions about our clinical insights.

Super Jem of a Reference

Juker D, McGill S, Kropf P, Steffen T. Quantitative intramuscular myoelectric activity of lumbar portions of psoas and the abdominal wall during a wide variety of tasks. Med Sci Sports Exerc. 1998 Feb;30(2):301-10