The Importance of Stupidity in Scientific Research: aka.... "How The Gait Guys feel much of the time"

We started The Gait Guys in some ways because despite all of the questions we asked  over the years,  from those who we all deemed as “those who are supposed to know”, we rarely got answers that we felt were sufficient for our thirst.

We had the research data that everyone else had, but no one was helping us put together a big picture that made sense or had reasonable clinical outcomes.  We are on a journey here at The Gait Guys. A journey based on the honesty and truth behind how the human body ambulates, the parameters that are necessary for it to work right, and what happens when things go wrong.

In the mean time, we share the conclusion statement of this journal article (link) .  It pretty much sums up how Ivo and I feel from time to time.  We hope you enjoy the reality of the statement.

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“Productive stupidity means being ignorant by choice. Focusing on important questions puts us in the awkward position of being ignorant. One of the beautiful things about science is that it allows us to bumble along, getting it wrong time after time, and feel perfectly fine as long as we learn something each time. No doubt, this can be difficult for students who are accustomed to getting the answers right. No doubt, reasonable levels of confidence and emotional resilience help, but I think scientific education might do more to ease what is a very big transition: from learning what other people once discovered to making your own discoveries. The more comfortable we become with being stupid, the deeper we will wade into the unknown and the more likely we are to make big discoveries.” -Martin A. Schwartz

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The key to the statement above was …. ” as long as we learn something each time”.  Otherwise, according to Einstein, we would be considered insane. 

Technology and medicine are moving at light speed our dear brethren. This is why we start our weekly podcast (LINK) with a neuroscience piece and link the new science and technology discoveries to gait and human movement. Because we would all be stupid not to look forward under the exponential growth paradigm that is today’s reality.

Have a good week everyone…….we have some great stuff queued up for the week, hope you get a little out of it all.

- We remain……..The Gait Guys……two “productively and comfortably stupid” gentlemen.

Vertical Oscilations, Danny Abshire and Running & Walking

https://www.facebook.com/photo.php?v=575995729092248&set=vb.111772995514526&type=2&theater

We saw this short 1 minute video by Danny Abshire on vertical movements in running (link is above). Here was the caption placed (by Runner’s Soul) with the video.

• “Danny Abshire, running guru and CTO of Newton Running, explains how vertical oscillation can impede any runner’s performance - did you know that lifting 6 inches with every foot strike can add almost 2.5 miles onto a marathon?”

We are currently trying to find the reference material he used (anyone please forward it to us at thegaitguys@gmail.com).  In theory it makes sense.  Here is an article that shows something a little different. This research article shows shows that minimizing the center of mass vertical movement increases metabolic cost because of the loss of passive mechanical energy from pendulum mechanics. Now, to be fair, apparently Danny was talking about increased distance and not metabolic cost. But what if distance was trumped by energy and time ?  Now there is a neat thought ! We doubt any marathoner would be upset if they ran further than the actual marathon distance but PR’d in the attempt.  One could easily postulate that the term “increased metabolic cost” would mean a slower run time because of the activity being inefficient.

• This study’s findings findings clearly demonstrate that human walkers consume substantially more metabolic energy when they minimize vertical motion.

In this study’s case, it refers to walking, however could it postulate to running as well?  Just something to think about.  As our reading on this topic continues, and as we find supportive and conflicting journal information we will post attachments here amongst our other articles to make sure our readership can see both sides of the peer reviewed research. In Danny’s, and everyone defense, we often find conflicting research in peer reviewed articles, it almost seems at though one can take a stance on any side of a medical topic and find an article to prove the theory, sadly often leaving us nowhere but spinning in place.

Anyhow, the summary of this peer reviewed article by Ortega concluded that :

“in flat-trajectory walking, subjects reduced center of mass vertical displacement by an average of 69% but consumed approximately twice as much metabolic energy over a range of speeds . In flat-trajectory walking, passive pendulum-like mechanical energy exchange provided only a small portion of the energy required to accelerate the center of mass because gravitational potential energy fluctuated minimally. Thus, despite the smaller vertical movements in flat-trajectory walking, the net external mechanical work needed to move the center of mass was similar in both types of walking. Subjects walked with more flexed stance limbs in flat-trajectory walking, and the resultant increase in stance limb force generation likely helped cause the doubling in metabolic cost compared with normal walking. Regardless of the cause, these findings clearly demonstrate that human walkers consume substantially more metabolic energy when they minimize vertical motion.”

In our summarizing of the article it indicated that more vertical motion seems to engage some of the energy conserving pendulum effects of the limbs. We know this happens in the spine. Serge Gracovetsky (“the Spinal Engine”) and many other researchers have discussed this energy conservation by the repetitive coiling and uncoiling of the spinal curves and loading/unloading of the spinal discs.   Here is the journal and abstract below.

Shawn and Ivo, The Gait Guys

________________________________

J Appl Physiol. 2005 Dec;99(6):2099-107. Epub 2005 Jul 28. Minimizing center of mass vertical movement increases metabolic cost in walking. Ortega JD, Farley CT. Source

Locomotion Laboratory, Dept. of Integrative Physiology, University of Colorado, Boulder, CO 80309-0354, USA. ortegajd@colorado.edu

Abstract

A human walker vaults up and over each stance limb like an inverted pendulum. This similarity suggests that the vertical motion of a walker’s center of mass reduces metabolic cost by providing a mechanism for pendulum-like mechanical energy exchange. Alternatively, some researchers have hypothesized that minimizing vertical movements of the center of mass during walking minimizes the metabolic cost, and this view remains prevalent in clinical gait analysis. We examined the relationship between vertical movement and metabolic cost by having human subjects walk normally and with minimal center of mass vertical movement (“flat-trajectory walking”). In flat-trajectory walking, subjects reduced center of mass vertical displacement by an average of 69% (P = 0.0001) but consumed approximately twice as much metabolic energy over a range of speeds (0.7-1.8 m/s) (P = 0.0001). In flat-trajectory walking, passive pendulum-like mechanical energy exchange provided only a small portion of the energy required to accelerate the center of mass because gravitational potential energy fluctuated minimally. Thus, despite the smaller vertical movements in flat-trajectory walking, the net external mechanical work needed to move the center of mass was similar in both types of walking (P = 0.73). Subjects walked with more flexed stance limbs in flat-trajectory walking (P < 0.001), and the resultant increase in stance limb force generation likely helped cause the doubling in metabolic cost compared with normal walking. Regardless of the cause, these findings clearly demonstrate that human walkers consume substantially more metabolic energy when they minimize vertical motion.

Ankle muscle spindles play a significant role in the control of posture and balance during the swing phase of locomotion

 

So tell us something we don’t know…

                                                                                                              
“The results provide strong evidence that the primary endings of ankle muscle spindles play a significant role in the control of posture and balance during the swing phase of locomotion by providing information describing the movement of the body’s COM with respect to the support foot. Our results also provide supporting evidence for the proposal that there are context-dependent changes in muscle spindle sensitivity during human locomotion."                                                                                    

• This study tells us what we already know: The muscles surrounding the ankle, especially of the leg you are standing on (the "stance” phase leg) provide important information to the central nervous system about both that leg AND the leg not on the ground (The “swing” phase leg).  Remember the central integration of things like the Crossed Extensor Response we have talked about in prior podcasts ?

• The implications are that if you have an ankle injury, this mechanism can be altered, resulting in loss of balance (or proprioception) as well as opening you up to greater (or additional) injury.
• The other implication is that the whole ball of wax is “situationally dependent”; meaning plastic and adaptable. Pretty cool !

The Gait Guys. Bringing you the latest and greatest, each and every post.

                                                                                       

                                                                                                                

 SOURCE:

Exp Brain Res. 2002 Mar;143(1):24-34. Epub 2001 Dec 18.

The effects of human ankle muscle vibration on posture and balance during adaptive locomotion.

Sorensen KL, Hollands MA, Patla E.

Source

Gait and Posture Laboratory, Department of Kinesiology, University of Waterloo, Ontario N2L 3G1, Canada.

Abstract

This study investigated the contribution of ankle muscle proprioception to the control of dynamic stability and lower limb kinematics during adaptive locomotion, by using mechanical vibration to alter the muscle spindle output of individuals’ stance limbs. It was hypothesised that muscle length information from the ankle of the stance limb provides information describing location as well as acceleration of the centre of mass (COM) with respect to the support foot during the swing phase of locomotion. Our prediction, based on this hypothesis was that ankle muscle vibration would cause changes to the position and acceleration of the COM and/or compensatory postural responses. Vibrators were attached to both the stance limb ankle plantarflexors (at the Achilles tendon) and the opposing dorsiflexor muscle group (over tibialis anterior). Participants were required to walk along a 9-m travel path and step over any obstacles placed in their way. There were three task conditions: (1) an obstacle (15 cm in height) was positioned at the midpoint of the walkway prior to the start of the trial, (2) the same obstacle was triggered to appear unexpectedly one step in front of the participant at the walkway midpoint and (3) the subjects’ walking path remained clear. The participants’ starting position was manipulated so that the first step over the obstacle (when present) was always performed with their right leg. For each obstacle condition participants experienced the following vibration conditions: no vibration, vibration of the left leg calf muscles or vibration of the anterior compartment muscles of the lower left leg. Vibration began one step before the obstacle at left leg heel contact and continued for 1 s. Vibrating the ankle muscles of the stance limb during the step over an obstacle resulted in significant changes to COM behaviour [measured as displacement, acceleration and position with respect to the centre of pressure (COP)] in both the medial/lateral (M/L) and anterior/posterior planes. There were also significant task-specific changes in stepping behaviour associated with COM control (measured as peak M/L acceleration, M/L foot displacement and COP position under the stance foot during the step over the obstacle). The results provide strong evidence that the primary endings of ankle muscle spindles play a significant role in the control of posture and balance during the swing phase of locomotion by providing information describing the movement of the body’s COM with respect to the support foot. Our results also provide supporting evidence for the proposal that there are context-dependent changes in muscle spindle sensitivity during human locomotion.

Mobium, Schmobium.

Here is the latest and greatest from the shoe manufacturer, Puma; it is their version of a more “adaptive” or “accommodative” shoe. They do not say minimalisitic, but rather it interferes minimally with walking or running. Good thing, because it has a pretty thick sole, superimposes a pretty substantial arch to the foot, and also has a fairly narrow toe box. Their runner is also a heel striker, at least at the beginning of the video.

Last time we checked, the plantar fascia was not “X” shaped and was present on the entire plantar surface of the foot, without an “apex” or “torque” in the center of where the medial longitudinal arch is located.

In referring to mirroring as they do in the video, we were wondering which muscles, bones and fat pads of the foot the “pods” actually mirror? And then there is those siping lines of the outsole, what’s with them and their location? The metatarsal heads form an arc at their distal end, where they articulate with the phalanges, as do the interphalageal joints (joints between the toes). This shoe’s lines arc less than we would expect.

They have the 5 metatarsal pads, not unlike the Newton. What happened at the toes?  Individuals with 3 toes should do well with those pods for the proximal and distal phalanges, but we think this is probably a limited market (wink, smile, wink).

We agree that “expansion” of a shoe is important so we think this shoe has a neat underlying idea. We would hope most folks aren’t wearing shoes that are too tight or short that their feet don’t have room to move inside the shoe.  We are also curious about the height of the lateral longitudinal arch, last time we looked there was not a tunnel shaped arch running under the foot.  The lateral longitudinal arch is always must more subtle and gentle.

Technically sound? We don’t think so, not from what we have discussed above. As for bringing something to the market that doesn’t exist that enhances the performance of the athlete? Well, it is unique, but performance enhancement remains to be seen. As for wrapping the shoe in a blanket of fabulous Puma design? It does have catchy colors and a great marketing campaign…

Just some off the cuff thoughts on our part. We would love a pair to dialogue out these thoughts and others. We are always open to being wrong, but we know our shoes and we know foot and shoe anatomy and biomechanics.  If you are from PUMA, contact us and send us a pair, we will be happy to eat our words if we are wrong in our cursory suppositions.

The Gait Guys. Helping you to make better footwear decisions and ask the questions no one wants to ask

all material copyright 2013 the Homunculus Group/ The Gait Guys. Please ask before using our material.

Podcast #26: Google shoes, shoe tech & indoor track biomechanics

Pod #26: The new Google Shoes, hamstring injuries in short track running and shoe tech.

podcast link: 

http://thegaitguys.libsyn.com/podcast-26-google-shoes-shoe-tech-indoor-track-biomechanics-and-injuries

iTunes link:

https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

Gait Guys online /download store:

http://store.payloadz.com/results/results.aspx?m=80204

other web based Gait Guys lectures:

www.onlinece.com   type in Dr. Waerlop or Dr. Allen  Biomechanics

Today’s show notes:

Two neuroscience pieces today which parlay nicely into last weeks podcast on kurzweils singujlarity

1- Google Shoes

http://www.huffingtonpost.com/2013/03/11/google-shoes_n_2853098.html

http://youtu.be/VcaSwxbRkcE

This weekend, at the annual South by Southwest conference in Austin, Texas, Google unveiled an early prototype of motion-sensing “smart shoes,” with an embedded speaker on the tongue of the shoe that can yell motivation at you when you’re being lazy, or encourage you when you’re being active. Google –which created the talking shoes in collaboration with Adidas,

2- The First Wireless, Implantable Brain-Computer Interface

http://gizmodo.com/5988342/the-first-wireless-implantable-brain+computer-interface-will-help-us-move-things-with-our-minds-on-the-go

3- Problems with small track counterclockwise running

J Mot Behav. 2012;44(1):63-8. doi: 10.1080/00222895.2011.645912. Epub 2012 Jan 13. Asymmetrical neural adaptation in lower leg muscles as a consequence of stereotypical motor training. Ogawa T, Kawashima N, Suzuki S, Nakazawa K.

Clin J Sport Med. 2000 Oct;10(4):245-50. Asymmetrical strength changes and injuries in athletes training on a small radius curve indoor track. Beukeboom C, Birmingham TB, Forwell L, Ohrling D.

4- Puma mobium shoe
http://youtu.be/9cOPMG-TDqw

5- from a Facebook readerI just saw you’re video on hammer toe stretching on tumblr. Great article with it too.

I’ve noticed that on my left foot, my 5^th toe doesn’t touch the ground at all when my foot is flat on the ground. It appears not to be doing any work and the pain under the head of my 5^th met is getting worse each week now.

6- another facebook question

• I’ve been doing your shuffle steps and moonwalk to increase my very inflexible ankles. Is there anything else I can do? I read the study and your blog post how stretching doesn’t work. My teammates have literally over twice the dorsiflexion I have and it really shows in my skating. If these two excersises are all that can be done what are the reps/sets/times per week recommendations?

7- Cushioned Heel Running Shoes May Alter Adolescent Biomechanics, Performance
http://www.sciencedaily.com/releases/2013/03/130319091420.htm

Shawn and Ivo

the gait guys

A blast from the past. Here’s one of our favorite posts, just in case you missed us a few years ago…

More Gait Guy Gait Gaffs: What it would look like if “The Flash”, ran with heel strike ? click here. Note the excellent anterior compartment use (nice ankle dorsiflexion and toe extension at terminal swing/ pre-impact) but heavy, nasty, heel strike. What is interesting here is that he has adopted a nice forward lean (ala. natural or chi running style) but when combining this with a heel strike gait you end up with an anterior pelvic tilt (which begins inhibition of the lower abdominals) and you then have to begin the power through phase in early-mid stance phase with the hamstrings. You need tremendous lower abdominal strength, and hamstring length and strength to run this way (go ahead, get up and try it running through your office ! let out a great “Yaulp” from the ensuing hamstring pull (ala Robin Willliams in Dead Poets Society) when you find out your abdominals are not strong enough to lean that far forward and still heel strike, without enough hamstring length (on second thought, just trust  us……although i know now we have challenged some of you). This is a medical disclaimer, dont do it !

The importance of hip extension

Watch this clip a few times. Pause it when it pauses. Have a look, then continue. Come back here when you are done.

Sometimes it seems like we keep saying the same thing over and over. Remember the 3 rockers? Heel rocker, ankle rocker and forefoot rocker. Look at the clip again. All three are there. We stopped the clip in a few places to show you HOW MUCH ankle rocker there was; probably a little TOO MUCH. As for hip extension, on the exam table, this gal had at least 15 degrees of hip extension. So what gives?

All that is lack of hip extension is not loss of ankle rocker, as you can see here. If we don’t have hip extension (she never even gets to zero) , then something else needs to do the brunt of the work. Here we see her quads and calves getting quite the workout here. But look closer and watch the lumbar lordosis (curve in the lumbar spine). See how it stiffens on impact and then extends as she goes through toe off? The motion HAS to occur SOMEWHERE. Guess we know why she has low back pain, especially on long runs.

The take home message?

We need 3 competent rockers for normal gait

We need adequate hip extension for normal gait

When one of the above mechanisms is not in place, compensation will occur somewhere else in the chain

The fix? Train her to use her hip extensors (glue max and medius) through gluteal awareness exercises. Things like having her palpate her glutes while walking and running.  Texas walk exercises. Retrain her foot strike to be more positioned under her body. Get her to extend and bring her arms back more. Stuff we talk about here all the time.

Ivo and Shawn. The Gait Guys. Extending your cerebral hips each and every post.

All material copyright 2013 The Gait Guys/ The Homunculus Group.

Some honest movements across the big toe. Things you need to know as a runner or walker.

Lets see how good you are at this gait game at this point. 

In the video above you should see two things: you should see me manually dorsiflexing / extending the big toe / hallux.  I am creating extension through the 1st metatarsal joint (1st MTP). Essentially I am passively engaging the Windlass Mechanism of Hicks.  This mechanism is essentially a biomechanical event that wraps the end of the plantar fascia over the metatarsal head and 1st MTP joint.  So, when a person raises the heel in gait a moment of dorsiflexion/extension occurs across the joint.  In the video you see me lifting the toe but in the closed chain event the toe stays on the ground and foot moves up and over the toe but the resultant motion at the 1st MTP is the same.  It is still dorsiflexion / extension of the big toe about the 1st MTP joint. 
This wrapping or winding of the plantarfascia around the joint causes the distance from the heel to the ball of the foot to shorten and thus creates an elevation of the arch of the foot (smarter than using an orthotic to push it up  huh !) but this mechanism also raises the talus and supinates the foot.  This action makes the foot more rigid and stable. After all, when you are raising the heel and progressing over the ball of the foot don’t you want a rigid lever to press off of ?!  Ask any sprinter and they will concur. However, this mechanism occurs in all folks who  have a relatively competent foot and 1st MTP joint. 
What you NEED to see in the video is the additional motion up the limb. Watch the video again. When the toe is extended (dorsiflexed) the arch rises but the limb also externally rotates. You can see this by the subtle drift of the blue dots on the limb.  We want and need this external rotation to occur at the hip and through the limb because remember, the limb was internally rotated as we passed our body mass over the foot. This is a normal gait phenomenon.
Here is what we want to you to ponder.  Imagine a person with:

•  a weak extensor hallucis mechanism (both longus and brevis: EHL, EHB)
•  a hallux rigidus where the toe does not fully extend to that magical 45+ degree range or
• if the arch of the foot is so far collapsed and pronated

IF any of these things go wrong, then a sufficiently rigid foot is not formed for push off propulsion, an incompetent arch results and insufficient talar motion and external limb rotation will occur. This means that several subsequent biomechanical events will/ may be compromised including but not limited to:

• contralateral arm swing
• sufficient engagement of the gluteals for stablization and propusion since optimal external hip rotation will not be met
• inadequate pelvis posturing for spine neutrality 
• etc. this is potentially a very very long list

Our take home point here is simple. You must have:

•  sufficient and relatively symmetrical bilateral big toe extenion (hallux dorsiflexion) to optimize the Windlass Effect
• you must have sufficient strength of the toe extensors to gain and stabilize this joint range at the 1st MTP joint
• you must have both of the prior 2 in order to properly posture the foot and arch for rigid terminal loading response
• and you must have all 3 to sufficiently externally rotate the limb at the hip to engage the propulsive components of the gait cycle.

There is so much more we could have added to this brief blog post, including hallux impingement, hallux valgus and bunion formation, supination insufficiency syndromes, tibialis posterior insufficiency syndrome, metatarsalgia etc.  The list is endless. 

Hallux dorsiflexion, both passive and active range of motion must be checked on every athlete and client you see. Otherwise gait is likely to be impaired locally and globally from subtle insufficiencies.

Shawn and Ivo
The Gait Guys

Podcast #25: Bionics, Arm Swing & Footwear

Great podcast today, #25. Wide range of topics today: the first truly bionic body part, technical shoe issues, GTO’s and more. 

podcast link: 

http://thegaitguys.libsyn.com/podcast-25-bionics-arm-swing-footwear

iTunes link: https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

Gait Guys online /download store:

http://store.payloadz.com/results/results.aspx?m=80204

Today’s show notes:

1. The First Truly Bionic Hand

http://www.independent.co.uk/life-style/gadgets-and-tech/news/a-sensational-breakthrough-the-first-bionic-hand-that-can-feel-8498622.html

“The first bionic hand that allows an amputee to feel what they are touching will be transplanted later this year in a pioneering operation that could introduce a new generation of artificial limbs with sensory perception.

2. Effects of toning shoes on lower extremity gait biomechanics

http://www.clinbiomech.com/article/S0268-0033%2813%2900010-7/abstract

Clinical Biomechanics, Jan 2013

3. Beware of trendy barefoot running shoes - you could end up with broken bones in your foot

Read more: http://www.dailymail.co.uk/health/article-2289725/Beware-trendy-barefoot-running-shoes–end-broken-bones-foot.html#ixzz2N5HOO0qk

http://www.dailymail.co.uk/health/article-2289725/Beware-trendy-barefoot-running-shoes–end-broken-bones-foot.html?ito=feeds-newsxml

• Advocates of barefoot running claim it can reduce injuries and back pain
• ‘Minimalist’ shoes such as these now account for 15% of sales
• But experts say many people suffer injuries by overdoing it early on
  
• Runners should make transition from regular trainers more slowly, they say

4. Foot strike and injury rates in endurance runners: a retrospective study.

Daoud AI, Geissler GJ, Wang F, Saretsky J, Daoud YA, Lieberman DE.
Med Sci Sports Exerc. 2012 Jul;44(7):1325-34. doi: 10.1249/MSS.0b013e3182465115.

Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.

5. Effects of foot strike on low back posture, shock attenuation, and comfort in running.

http://www.ncbi.nlm.nih.gov/m/pubmed/23073217/
Med Sci Sports Exerc. 2013 Mar;45(3):490-6

CONCLUSION: Change in foot strike from RFS to FFS decreased overall ROM in the lumbar spine but did not make a difference in flexion or extension in which the lumbar spine is positioned. Shock attenuation was greater in RFS. RFS was perceived a more comfortable running pattern.

*it seems to becoming a question as to what you are doing with the body parts at impact……..where it be you are RFS or FFS.  Do you have the ability to protect the parts in varying mechanical stressful positions.

6. Hey guys, Dr. Ryan:

I just listened to Pod 23 and Ivo you mentioned sagittal curves not developing until after birth..  There is evidence they begin to develop in-utero.  Here is an article excerpt and link to it.

 

"In many anatomy texts, it is often claimed and/or assumed that the cervical lordosis is a secondary curve and is not present during intra-uterine life. However, as early as 1977, Bagnall et al³ demonstrated that the cervical lordotic curve is formed in intrauterine life (9.5 weeks). In 195 fetuses, Bagnall et al³ found that by 9.5 weeks, 83% of fetuses have a cervical lordosis, 11% have a military configuration, and only 6% of fetuses are in the typically described kyphotic position of the cervical spine. This means that by 9.5 weeks, 94% of the fetuses are starting to use their posterior cervical muscles to pull the cervical curve away from the fetal “C”-shape. Fetuses have a cervical lordosis before birth, however, the lordosis increases during post-natal life at ages 3 months-9 months as the infant raises his/her head and begins to sit up.^4”

http://www.chiropractic-biophysics.com/clinical_chiropractic/2011/2/11/pediatric-cervical-lordosis-values-disorders-and-interventio.html

REFERENCES

1. Harrison DD, et al. Spine 1996; 21: 667-675.
2. Harrison DD, et al. Spine 2004; 29:2485-2492.
3. Bagnall KM, et al. J Anat 1977;124:791-802.
4. Kure S. J Tokyo Med Collage 1972;30;453-470.
5. Kasai T, et al. Growth. Spine 1996;21:2067-2073.
6. Harrison DE, Harrson DD, Haas JW. Evanston, WY: Harrison CBP Seminars, Inc., 2002, ISBN 0-9721314-0-X.
7. Shatz A, et al. Acta Anat 1994;149:141-145.
8. McAviney J, et al. J Manipulative Physiol Ther 2005;28:187-193.
9. Bastecki A, et al. ADHD: A CBP Case Study. J Manipulative Physiol Ther 2004; 27(8):e14.

7. “Dynamic Arm Swing in Human Walking, (http://www.ncbi.nlm.nih.gov/pubmed/19640879) where it was determined that normal arm swinging required minimal shoulder torque, while volitionally holding the arms still required 12% more metabolic energy. Among measures of gait mechanics, vertical ground reaction moment was most affected by arm swinging and increased by 63% without it.
* brings up issues of shoulder pathology……rot cuff, frozen shoulder, carrying a purse, water bottle etc


8. Winter foot wear:
We like Steger Mukluks…….youtube video   "gait guys mukluks”

9. Versions: one of the more difficult concepts to grasp…………..here is a Q from a FB reader

• Does retroversion mean this child will automatically grow up with abnormal mechanics - leading to possible knee foot hip back issue etc? Is there a fix to prevent such without an ortho’s bone saw?

   

  10. The role of GTO’s in plyometric exercises.

“Those guys are perfect examples of pure genius.” - Mikhail Baryshnikov

***** WAIT ! Read the blog post FIRST, then watch the clip. Trust us.

We are going to start today’s blog post with a disclaimer.  “Do not attempt what these fellas do in the last moments of this video, particularly the scene on the stairs.”

Almost everyone on the face of this planet can walk, and most of those can also run as well.  It is basically all about putting one foot in front of the other and trying to maintain some sense of balance and stability over the stance limb without falling over. For some however, this is their greatest challenge of the day, walking.  Whether it be from an arthritic hip or knee or a neuro-degenerative disease, some folks see walking as their greatest physical challenge on a daily basis. 

For the able bodied folks, dance is another matter when compared to walking or running. Dance is about as far in the extreme opposite direction as one can get from simple walking gait or running. Here at the Gait Guys we know this intimately. In our mission to better understand human locomotion we continue to personally delve into tasks of complex motion, for it is only through studying the difficult that the beauty of the simple shines through.  After committing 3 years to investigating and learning smooth and latin dance with some truly amazing teachers we can say with some strong personal conviction, dance is different.  Footwork can be very complex in dance, as it can at times in many sports, but one thing is for certain they are not the same.  In dance the foot steps are consciously calculated to the beat of the music, this does not occur in any other sport and thus the steps and lower limb movements in most sport are less calculated and important than when it comes to fixed techniques, procedures and protocols as in dance.  Rumba steps are different from cha cha, waltz, foxtrot, swing, salsa, mambo, hustle, tango etc. Each dance has unique steps and must be able to be performed at varying tempos, at the very least. Oh, least we forget to mention that you usually have a partner you must choreograph the movements with, taking turns moving forward, backward or spinning. In contrast, when Michael Jordan is spinning off of a pick-and-roll driving to the hoop he is not exactly consciously calculating footwork at a ¾ time for exampleor making sure that there was a specific foot and leg action that was premised on the movement. The goal and demand is different in dance. 

There are no particular learning issues on this blog post today, just sit and watch in amazement how precise and clean these fellas are. Over the three years dancing I Iearned all that I could regarding the complexities of foot and limb work from the 8+ dances presented to me. I gleaned many insights into the complexities of human movement and in the process stole some pretty amazing exercises for foot and lower limb rehabilitation and testing. Perhaps, what I began to respect more than any other thing was the level of athleticism that dancers achieve, speed, precision, coordination, agility, flexibility, strength, grace and so much more.  It is clear to us now why some of the best athletes in the world add some components of dance to their workouts to enhance their sport performance and get an edge on their competition.

So, now sit back and try to truly appreciate the speed, precision, coordination, agility, flexibility, strength, grace and more of these two fellas. I dare one can find many athletes on this planet that will try what they successfully do down those stairs. And because of that, I almost dare anyone to say they are not athletes to the highest level. Try not to get caught up in the entertainment of the video, rather, study intently the complexities of what these two fellas are about to do … . . and while doing it to music, in synchronization with eachother, they keep perfect timing the whole way through. And for an even more amazing trip, cover up their upper bodies and just watch their feet and legs.

“Fayard and Harold Nicholas were a fantastic set of flash-dancers who performed as the Nicholas Brothers. Born seven years apart, the brothers performed for decades on stage and screen, later teaching dance to Michael and Janet Jackson, among many others. In the performance below from Stormy Weather, many of their trademark moves are on display – jumping down stairs into splits, sliding up from splits without using hands, and gleefully jumping through orchestra stands, while tap-dancing in unison. This is downright amazing. According to The Kid Should See This:

• Fred Astaire once called this performance “the greatest dance number ever filmed.” Mikhail Baryshnikov said, “Those guys are perfect examples of pure genius.”

And to finish off here today, we have some new things to begin sharing in the coming weeks.  My 3 year commitment to dance has run its course, for now. And a new 3 year commitment has begun. Stay tuned to find out where the new inspirations will be coming from, its is about as far from dance as one can get but the movements to some are just about as beautiful and complex. Here is a hint, "Where you at Georges?” (you curious folk can google it).

Stick with the Gait Guys, our journey with you into the mysteries of human movement have only just begun.

“Where you #@%*#  at Georges !? ” 

Shawn and Ivo,

The Gait Guys

More Proof that the Cross Over Gait has Pathologic Issues for Runners / Athletes.

We have referenced below yet another article in our 2 year long soap box rant that the cross over gait has many negatives to it.  Two weeks ago we discussed the issues in greater depth in podcast # 23 (link: http://thegaitguys.tumblr.com/post/43424418001/podcast-23-neurology-of-walking-babies-dialogues-on) and further in a most recent blog post here (link: http://thegaitguys.tumblr.com/post/44060333371/step-width-alters-iliotibial-band-strain-during).

By this point pretty much everyone should be aware that pelvis width and femoral shaft angle orientation (Q-angle) parlays consistently into knee posturing and thus patellar tracking.  Loosely it goes to say a wider pelvis often makes for a knee tracking challenged environment.  But today’s reference article takes this a little deeper.

Running mechanics always have to be approached from above the knee and below. If the foot collapses too far inwards the internal spin put on the tibia will drag the knee inwards and generate a mal-tracking environment.  And from above, if the gluteal muscles are underperforming they cannot assist in holding the femur in sufficient abduction and external rotation to prevent excessive internal spin from above, thus also enabling a mal-tracking environment from developing.  These are well established theories with plenty of research and years to back them up.  The verbiage “proximal control for distal control” holds. Or, “proximal stability for (proper) distal mobility” also holds true but one needs to never forget about the critical importance of the far distal (foot/ankle) foundational support. 

In today’s study from 2012 there is really nothing earth shatterning to most of our readers but we wanted to again bring these thoughts are results to you and keep the cross over gait in your ever-present mind.  The conclusions of this Harvard study were predictable, that being:

“the finding of greater hip adduction in female runners who develop PFP is in agreement with previous cross sectional studies. These results suggest that runners who develop PFP utilize a different proximal neuromuscular control strategy than those who remain healthy. Injury prevention and treatment strategies should consider addressing these altered hip mechanics.”

So the study eludes to the fact that not only is it about the anatomy of the parts but also about the functional control of the parts. Without adequate control from above and support from below the knee, it will be difficult to control a largely uni-planar joint (the sagittal flexion/extension of the knee hinge) when the support of a multi-planar joint complex (foot/ankle) from below is insufficient and the control of a multi-planar joint complex above the knee (hip/pelvis) is insufficient.  When one or especially both are compromised the knee will be compromised. It may take weeks or months or even longer for the process to render joint change or pain but without sufficient biomechanics the system is likely to fail. And further more, one needs to realize that shoes and orthotics often are an incomplete (and very often an insufficient and inadequate) remedy.  One must “earn it to own it”. 

If you find you are new to our work and want to catch up on the Cross Over gait topics we have covered previously, try starting here (link: http://thegaitguys.tumblr.com/search/cross+over) and here (link: http://thegaitguys.tumblr.com/search/cross+over+gait).  We are likely to continue to build on this disfunctional paradigm.

Shawn and Ivo
The Gait Guys

Reference:

Med Sci Sports Exerc. 2012 Dec 27. [Epub ahead of print] Prospective Evidence for a Hip Etiology in Patellofemoral Pain. Noehren B, Hamill J, Davis I. Source

1Division of Physical Therapy, University of Kentucky, Lexington, KY 2Department of Exercise Science, University of Massachusetts, Amherst, MA 3Spaulding National Running Center, Harvard University, Cambridge, MA.

Abstract PURPOSE:

Patellofemoral pain (PFP) is the leading cause of knee pain in runners. Proximal and distal running mechanics have been linked to the development of PFP. However, the lack of prospective studies limits establishing a causal relationship of these mechanics to PFP. The purpose of this study was to prospectively compare running mechanics in a group of female runners who went on to develop PFP compared to healthy controls. It was hypothesized that runners who go on to develop PFP would exhibit greater hip adduction, hip internal rotation, and greater rear foot eversion.

CONCLUSIONS:

The finding of greater hip adduction in female runners who develop PFP is in agreement with previous cross sectional studies. These results suggest that runners who develop PFP utilize a different proximal neuromuscular control strategy than those who remain healthy. Injury prevention and treatment strategies should consider addressing these altered hip mechanics.

The Truth about Hammer Toes and the myths about the classically employed stretch to reduce them.

Stretching often feels good but sometimes the shortness or tightness in a tissue is not the focal point problem and it may be present as a neuro-protective phenomenon. Reducing the shortness may make an area vulnerable unless the primary problem driver is resolved concurrently or even prior.

Toes which are chronically hammered, like the ones mimicked here in the video, can shorten the capsule of the metatarsal phalangeal joint (particularly the flexor side of the joint). Hammer toes usually show a classic pairing of shortness: short extensor digitorum brevis (EDB)and flexor digitorum longus (FDL) within an environment that was likely the hammer toe precursor, that being weak extensor digitorum longus (EDL) and weak flexor digitorum brevis (FDB) as well as other functional problems locally within the foot and possibly more proximally into the ankle and lower limb/pelvis. When the capsule has been chronically shortened over time from such a scenario, the stretch shown in the video can certainly be helpful to restoring normal joint range, function and centration but this would only hold true if the capsule shortness is dorsally (top side of the joint). Hammer toes will present with plantar/flexor capsule retraction typically.

However, we need to return to the bigger question at this point, “what causes toes to curl and hammer such as suggested in this video” (besides plantar contraction of the capsule, as we just discussed) ?

Would it make sense that it was both extensors of the toes (extensor digitorum longus EDL, extensor digitorum brevis EDB) that were both short ? First of all this is not the pairing of muscle shortness in hammer toes as revealed above. And secondly,  if these two (EDL, EDB) were the culprit and they were short they would cause extension of the distal part of the toe as well because they attach to the distal part of the phalanges. Again, hammering of the toes would not occur if it were the both extensors that were short. In hammer toes the EDL is weak, not short. The EDB however attaches to the proximal phalanyx of the toes and its shortness is a major culprit in hammer toe presentations. And when a person pairs the EDB shortness with long flexor shortness (flexor digitorum longus-FDL) the hammer toe results. So, technically, to reduce a hammer toe one should stretch the short extensor (EDB) and the long flexor (FDL) and the flexor part of the capsule if it is retracted.  The single stretch shown in this video is not sufficient to achieve the goal we interpreted as outlined. And again, restoring all of the other functional problems along the kinetic tree that allowed for this hammering strategy to initiate in the first place.

In summary, as shown in the video, is this a bad stretch? Not necessarily, just know what you are stretching and why. In this case you are stretching the EDL and the EDB and the dorsal (top of) capsules of the digits.  And if that is your goal, for whatever reason, then this stretch is fine. However, as we hope we have outlined here, the combined EDL and EDB shortness and dorsal capsule retraction are not the source of hammer toes. Again, if that were the case the toe would be straight and pointed upwards and thus not presenting as hammer toes .  In our explanations here, the extensor digitorum longus is weak and lengthening an already weak muscle like the EDL would not be a great idea.

The Gait Guys. Just helping to clarify some of the specifics and errors of some of the information on the world wide web.

all material copyright 2013 The Gait Guys/The Homunculus Group. All rights reserved.

This one is important. The stinky gait.

It is the end of the week folks. And that means it is time for a post recycle. As we approach 800 blog posts it is increasingly difficult for the new members to the gait brethren here at The Gait Guys to catch up. So we make Fridays a recap of an oldie but a goodie. And today’s choice STINKS (You will understand in a moment).  This one has an important preamble so we hope that  you will take the 5 minutes to watch this video and read what we believed was important to write. It parlays nicely with yesterday’s blog post on muscles.

Enjoy this one folks, and have a great weekend. We took a week off of podcasting this week, our government wants us to pay our taxes again, so it was off the the accountants we went (killing and screaming of course). Shesh ! The never of them !!!!!   We hope to be recording a new podcast over the weekend.

The Stinky Gait:  link: 

http://thegaitguys.tumblr.com/post/5014037442/gait-gaff-time-gaff-verb-tr-to-stand-or-take

Shawn and Ivo, The Gait Guys

Activating Weak Muscles: What are you really doing to your athlete ?

What we see is almost never the problem, we see their strategy to compensate. We all need reminded of this on occasion.

If an athlete is falling apart at the end of a workout it is possible he COULD either not have enough strength and endurance in the primary central pattern or in the compensation pattern that he is employing.

Without precise neuronal pattern assessment and detailed muscle testing we are all guessing. If a client keeps training on the pattern he has available to him, he is just reinforcing it further and too much eventual strength on a faulty pattern is what leads to the big injuries late in the season as strength peaks.

We worry when those with not enough education or experience in this field utilize activation on their athletes. It is no one’s fault, facts are just facts.  We just don’t like people to get incomplete care.  Often times, trainers, coaches and even some doctors and therapists are simply short on time and a few moments of local assessment and activation quite possibly can lead one to forks in the road that one might not want to go down. Trust us, we have made these same mistakes early on and it is likely we still make them from time to time, we are just as human.

Just because a muscle shows you it is weak on a challenge does not mean it should be activated, activated at that particular time or the primary site of activation focus. Neurologic inhibition is not always a local phenomenon, it can and often does, originate from a change in the central integrated state of the organism. Furthermore, muscle strength assessment in any plane, no matter how specific you try to be, is never delivered by a solitary muscle rather there is a team effort to stabilize around the joint(s) challenged.  Remember, when you find something weak, it is talking to you and saying “i am weak because the parameters for my optimal function and joint stability are not being met.” If you activate that muscle it is really a far cry different than using the old analogy “no pain no gain”.  Meaning, making that muscle spring to life from a local activation does not mean you have addressed the problem, rather you may have just forced a wounded player to go back on the field when what it needs is a deeper solution. Stimulation of that local muscle can change the ascending and descending integrated state of the organism and may offer many changes in many areas, some in the area you wish and some other changes you may not wish to occur.  It is like reprimanding the screaming kid in the back of a car when there is someone else sitting back there with 2 bloody fists. We have extended our assessments to be almost a third to a half of a 45 minute visit now. And making the activation as precise as we can. In reality, we realize that many do not have the muscle and neuro background necessary to be good at this game, heck we are still learning on our end.  So, this makes it very difficult for anyone, especially when the clock is short, to get it right. Better results come from being more precise and understanding the grander scope of the story the body is telling us from the examination.  We say this because, as we have also found in our work, you very well may be activating weaknesses that are funded by a faulty pattern.  So by activating what seems to be weak one could be perpetuating and reinforcing a secondary and less effective pattern.  Remember, a weakness is present for a reason and quite often because a primary pattern is not engaged or appropriate motor skill has not been reestablished.  Thus by activating what seems to be weakness in muscles one is essentially just resetting a breaker switch, and continuing to fund  and reinforce a faulty pattern or circuit,  instead of finding out where in the loop the problem exists that keeps blowing the fuse.

Shawn and Ivo, the gait guys

____________________

Here is a supportive article to give our commentary some “legs” to stand on. A locally weak ankle from a sprain or strain can change the whole picture.

Chronic ankle instability alters central organization of movement.

Haas CJ, Bishop MD, Doidge D, Wikstrom EA. Am J Sports Med 2010 Apr;38(4):829-34.

Epub 2010 Feb 5. Department of Applied Physiology and Kinesiology,University of Florida, Gainesville, Florida, USA.

This would be an excellent example of restoring function (ie skill)  for rehab, rather than just increasing strength. If fine motor control is not mastered 1^st and you do not change the central pattern, you are carving a turnip with a chainsaw.

We are…. The Gait Guys

OK Folks

Take a look at these pics for a moment, then come back and read.

Ready? Lets see how much you remember about torsions and versions. Take a look at this child that was brought in by their parent (legs were too short to drive themselves : )  ) They were wondering if the child needed orthotics. What do we see?

top left photo: legs are in a neutral position. note the position of the knee (more specifically the tibial tuberosity and patellae can sometimes fake you out. ( OK, maybe not you, but they can sometimes fake SOME people out). The plane of the 2nd metatarsal is LATERAL to the tibial tuberosity, This is EXTERNAL TIBIAL TORSION; it appears greater on the (patients) right (look also at the left lower leg in the center picture as well, it has less torsion). Note also the lower longitudinal arches bilaterally (they are typically higher in non-weightbearing but in children this young they are typically lower in the early stages).

top right photo: I am fully internally rotating the right lower leg and hip. Note the position of the knee; it does not rotate as much as you would expect (normally 40 degrees) when compared to the distance the foot seems to have travelled. This hip is RETRO-TORSIONED (remember we are born anteverted about 40 degrees, which decreases approximately 1.5 degrees per year to puberty, resulting in an 8-12 degree angle in the adult. If you need a review, go back and read the February 27th post). Go back and read our 5 part series on Versions and Torsions (“Are you Twisted ?”).

Center photo: I am fully externally rotating the right leg. Note that range of motion is much greater than internal rotation and exceeds 40 degrees. This supports the previous paragraph, retro-torsion.

Bottom left: I am fully internally rotating the left lower leg. It appears normal  with about 40 degrees (or more) of internal rotation. This femur is NORMAL or has NORMAL FEMORAL VERSION.

Bottom right: I am externally rotating the left leg. Motion appears to mimic internal rotation and is approximately equal. This supports the previous paragraph as NORMAL FEMORAL VERSION.                               

In summary:

• External tibial torsion, R > L
• flattened longitudinal arches
• Right femoral retrotorsion
• Left femoral version, NORMAL

Well, what do you think? Are orthotics going to help this kiddo? No, probably not, they may even make the problem worse, by slowing derotation of the talar head, forcing them into more permanent varus of the forefoot.                                                                                                           

How did you do? Can you see now why torsions and versions (the degree of “twistedness” of a limb is so important? They help you understand skeletal development and help you to make clearer decisions.

The Gait Guys. Twisted in a good way. Versioned but not torsioned.

all material copyright 2013 The Gait Guys/The Homunculus Group. all rights reserved. please don’t use our stuff without asking : )

The funny problem with the stairs at Brooklyn’s 36th Street subway. Why we trip..

  At Brooklyn’s 36th Street subway stop, one of the steps is slightly higher than the others. Stairs have a standardized Rise and Run and when this is altered, specifically the Rise, funny things happen. Filmmaker Dean Peterson set up his camera to capture the stumbles and the video can be seen here http://vimeo.com/44807536 and above on our blog.

The dangerous step, it turns out (which has since this video been repaired), is apparently a half-inch higher than the others. Stairway design guidelines vary within a small range.  Guidelines call for risers to be a minimum of 6 inches and a maximum of 7 ¾ inches. The allowable variance between steps is 3/8 of an inch depending on the source you seek.

(The general rule (in the US) is 7-11 (a 7 inch rise and 11 inch run). More exactly, 7 ¾ rise and an 11 ½ inch run, although some people will use a run of as little as 9 inches.)

This is a perfect example of how sensitive and predictive the human body is with all of its amazing joint position sense receptors.  But there is more to it than a simple step height differential. Read on.

There are multiple demands that stairs place on the neuro-musculoskeletal system. There are needs for input from the somatosensory, visual, and vestibular systems at various stages in the task. Some of these collaborating systems deteriorate with the aging process making the failure of stair negotiation a legitimate risk for the elderly or those that are handicapped in one of the 3 primary systems noted above. Studies (see references below) strongly link impairments in the visual system to safe stair  negotiations.  The Buckley study found that the mediolateral balance during stepping up and down stairs (single limb support stability) was significantly reduced (especially stepping down) by blurred vision highlighting the critical necessity of vision in stepping dynamics.  Hence, one must be aware of people traffic on steps, if a stairway is dense with traffic the ability to gain the visual cues of the successive stairs is paramount. The next time you are in a school or subway stairwell notice the undercurrent of your discomfort may be from the inability to see enough steps in front of you.  Letting the person ahead of you clear some distance is a must, especially if you are vision impaired, elderly, wearing dark tinted glasses or are without the ability to use other cues such as railings (ie. adding a tactile feedback system to satisfy the impairment of visual cues). 

There are other user created impairments that we may be unaware of consciously. In the Miyasike-daSilva study it was determined that as participants approached and walked stairs, gaze was within 4 steps ahead of their location indicating that individuals often rely on spatial cues from prior experience or from other visual cues to obtain the necessary information from the environment.  Thus, one must be careful carrying something such as a baby, groceries or laundry basket in front of you thus impairing the lower visual field. We have all carried something up or especially downstairs and either thought we were on the last step or found we had one more to go and found ourselves either stumbling forward or hyperextending our knee as we lurch down onto the unexpected step.  In the video you will see a great example of this forward catch as one of the ladies is carrying a baby in front of her, luckily she makes the correct saving motor choice.  Being able to plan/control landing mechanics are significantly different when the visual system is locked out or impaired from stepping tasks. Timmis found that the contribution of information from the lower visual field of gaze in controlling the landing strategy occurs predominantly prior to or during movement initiation of the foot and limb and that ‘online’ or immediate vision is used only in the latter portion of the descent phase to fine tune the step landing. Buckley found that under visual impairments subjects used the cautious strategy of keeping their weight back on the trail limb longer making weight transfer noncommittal affording the time necessary for the lead limb to fish around for the next step.

There is so much involved in negotiating stairs and steps, even level ground walking. There are many cues we have learned to subconsciously glean information from. Sadly, when we begin to age and lose proprioceptive or visual information things begin to fall apart. The system is so sensitive and intuitive. This is why when someone changes the ground level, or the height of a step as in this video, the system fails even the best of us who have all of our faculties about us. And, we learn more about gravity at that moment than we wish to learn.

Shawn and Ivo, The Gait Guys

References:

1. J Am Geriatr Soc. 2000 May;48(5):567-80. Startzell JK,Owens DA , Mulfinger LM, Cavanagh PR .Stair negotiation in older people: a review.

2. Gait Posture. 2005 Oct;22(2):146-53.Buckley JG,Heasley K,Scally A,Elliott DB.The effects of blurring vision on medio-lateral balance during stepping up or down to a new level in the elderly.

3. Exp Brain Res. 2009 May;195(2):219-27. Epub 2009 Mar 31.Timmis MA,Bennett SJ,Buckley JG .Visuomotor control of step descent: evidence of specialised role of the lower visual field.

4. Exp Brain Res. 2008 Jan;184(2):223-32. Epub 2007 Aug 29.Buckley JG,MacLellan MJ,Tucker MW,Scally AJ,Bennett SJ.Visual guidance of landing behaviour when stepping down to a new level.

5. Exp Brain Res.2012 Sep 22. [Epub ahead of print]Shinya M,Popescu A,Marchak C,Maraj B,Pearson K.Enhancing memory of stair height by the motor experience of stepping.

6. Exp Brain Res. 2011 Mar;209(1):73-83. Epub 2010 Dec 25.Miyasike-daSilva V,Allard F,McIlroy WE .Where do we look when we walk on stairs? Gaze behaviour on stairs, transitions, and handrails.

7. PLoS One.2012;7(9):e44722. Epub 2012 Sep 6.Does it really matter where you look when walking on stairs? Insights from a dual-task study. http://www.ncbi.nlm.nih.gov/pubmed/22970297Miyasike-Dasilva V,McIlroy WE.PMID:22970297[PubMed - in process] PMCID:PMC3435292 Free PMC Article