How do humans run faster ?

Runners appear to use two different strategies to increase their speed according to this article we are appreciating by Dorn, Schache and Pandy

In specific observance of the lower limb muscles,
"Humans run faster by increasing a combination of stride length and stride frequency. In slow and medium-paced running, stride length is increased by exerting larger support forces during ground contact, whereas in fast running and sprinting, stride frequency is increased by swinging the legs more rapidly through the air". . . . .
"For speeds up to 7ms–1, the ankle plantarflexors, soleus and gastrocnemius, contributed most significantly to vertical support forces and hence increases in stride length. At speeds greater than 7ms–1, these muscles shortened at relatively high velocities and had less time to generate the forces needed for support. Thus, above 7ms–1, the strategy used to increase running speed shifted to the goal of increasing stride frequency. The hip muscles, primarily the iliopsoas, gluteus maximus and hamstrings, achieved this goal by accelerating the hip and knee joints more vigorously during swing."

Muscular strategy shift in human running: dependence of running speed on hip and ankle muscle performance
Tim W. Dorn, Anthony G. Schache and Marcus G. Pandy*
Department of Mechanical Engineering, University of Melbourne, Victoria 3010, Australia. The Journal of Experimental Biology 215, 1944-1956
© 2012. Published by The Company of Biologists Ltd
doi:10.1242/jeb.064527

Podcast 143: Future of movement, Running Cadence. Plus: gait rehab, eye control, plantar fascia talk

Topics:


Links to find the podcast:
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Our website is all you need to remember. Everything you want, need and wish for is right there on the site.
Interested in our stuff ? Want to buy some of our lectures or our National Shoe Fit program? Click here (thegaitguys.com or thegaitguys.tumblr.com) and you will come to our websites. In the tabs, you will find tabs for STORE, SEMINARS, BOOK etc. We also lecture every 3rd Wednesday of the month on onlineCE.com. We have an extensive catalogued library of our courses there, you can take them any time for a nominal fee (~$20).

Our podcast is on iTunes and just about every other podcast harbor site, just google "the gait guys podcast", you will find us.

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Show notes:

The future of human movement control ?
https://www.zerohedge.com/news/2019-01-01/zuckerberg-funds-wireless-mind-control-using-game-changing-brain-implants

Really interesting study: in-race cadence data from world 100K champs. Fatigue matters less than expected;
https://www.outsideonline.com/2377976/stop-overthinking-your-running-cadence?utm_medium=social&utm_source=twitter&utm_campaign=onsiteshare

A new study shows a majority (82%) of adolescent patients presenting with FAI syndrome can be managed nonoperatively, with significant improvements in outcome scores at a mean follow-up of two years: ow.ly/GXtC30n49nc pic.twitter.com/dyr4f6pEOU

Gait Rehab
https://academic.oup.com/ptj/article/88/12/1460/2742171
" Rehabilitation of gait in PSP should also include oculomotor training because the ability to control eye movements is directly related to the control of gait and safe ambulation. Vision plays a critical role in the control of locomotion because it provides input for anticipatory reactions of the body in response to constraints of the environment. Anticipatory saccades occur normally in situations that involve changing the direction of walking17 or avoiding obstacles.18 When downward saccades are not frequently generated during obstacle avoidance tasks, there is an increase in the risk for falling. Di Fabio et al19 reported that elderly people at a high risk for falling generated fewer saccades than their low-risk counterparts during activities involving stepping over obstacles. In addition, foot clearance trajectories were asymmetric in the high-risk group, with the lag foot trajectory being significantly lower than the lead foot trajectory. Similar behavior has been observed in patients with PSP during stair-climbing activities. Di Fabio et al20 recently reported that patients with severe oculomotor limitations had a lower lag foot trajectory than those with mild oculomotor limitations. "

Eye movements:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4932064/
" The content of the eye movement program was as follows: First, a picture card was shown to the patient, and then mixed with 20 other cards and spread face up on the desk. The patient was instructed to find that one card. This task was repeated approximately 20 times. Second, the therapist moved a baton slowly while drawing curves and the patient was instructed to keep his or her gaze fixed on the tip of the baton. In this task, the distance between the baton and the patient was maintained at approximately 1 m and the task was performed for approximately five minutes. Third, the patient was instructed to shake his or her head laterally as quickly as possible and a letter card with letters written upside down was presented to the patient to read. This task was repeated approximately 10 times. Fourth, the therapist moved a baton slowly from a point approximately 5 cm away from the patient to a point approximately 50 cm away and the patient was instructed to keep his or her eyes on the baton. This task was performed for approximately five minutes. The experimental group underwent eye movement training while the control group underwent gait training for 20 minutes per session, five times per week for six months in total."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3259492/

Plantar fascia loads higher when forefoot striking . . . .
https://www.sciencedirect.com/science/article/pii/S0021929018308959
Foot arch deformation and plantar fascia loading during running with rearfoot strike and forefoot strike: A dynamic finite element analysis
Tony Lin-WeiChen et al

High pronation was associated with 20-fold higher odds of injury than neutral foot posture
Association between the Foot Posture Index and running related injuries: A case-control study
AitorPérez-Morcillo et al
https://www.sciencedirect.com/science/article/pii/S0268003318304303

movement, gait, thegaitguys, running, cadence, step length, stride length, eye movements, rehab, gait analysis, gait problems, pronation, plantar fascia,

When one foot is shorter, and smaller. Gait thoughts to consider.

This person had a congenital “club foot” at birth also know as congenital talipes equinovarus (CTEV). It is a congenital deformity involving one or both feet. In this case it affected the right foot (the smaller one).
Foot size is often measured with the Brannock device in shoe stores, you know, the weird looking thing with the slider that measures foot length and width. In this case, the right heel:ball ratio, the length from the heel to the first metatarsal head, is shorter. The heel:toe length is also shorter, nothing like stating the obvious ! IF they are shorter then the plantar fascia is shorter, the bones are shorter, the muscles are smaller etc.

So, the maximal height of the arch on the right when the foot is fully supinated is less than that of the left side when also fully supinated (ie. during the second half of the stance phase of gait). Even with maximal strength of the toe extensors which we spoke of yesterday will not sufficiently raise the arch on the right to the degree of the left.

Thus, this client is very likely to have a structural short leg. Certainly you must confirm it but you will likely see it in their gait if you look close enough.
Also, you must remember that the shorter foot will also spend fractionally less time on the ground and will reach toe off quicker than the left. This may also play into a subtle limp.
This client may have a mal-fitting shoe, the right foot will swim a little in a shoe that fits correctly on the left. You may be easily able to remedy all issues with a cork full length sole insert lifting both the heel and forefoot. This can negate the shoe size differential, change the toe off timing and remedy much of the short leg issue. You will know that the right foot at the metatarsal-phalangeal joint bending line will not be flexing where the shoe flexes on that right foot. The Right foot will be trying to bend proximal to the siping line where the shoe is supposed to naturally bend. This will place more stress into that foot. This brings up the rule for shoe fit: never size a persons shoe by pinching the toebox to see if there is ample room, the shoe should be fit to meet the great toe bend point to the flex point of the shoe.
Strength of muscles is directly proportional to the cross sectional area of the muscle. With smaller muscles, this right limb is very likely to be underpowered when compared to the left.
All of these issues can cause a failure of symmetrical hip rotation and pelvic distortion patterning.
Altered arm swing (most likely on the contralateral side) is very likely to accommodate to the smaller weaker right lower limb. Do not be surprised to hear about low back pain or tightness or neck/shoulder issues.
A shorter right leg, due to the issues we have discussed above, will place more impact load into the right hip ( from stepping down into the shorter leg) and more compressive load into the left hip (due to more demand on the left gluteus medius to attempt to lift the shorter leg during the right leg swing phase). This will also challenge the pelvic symmetry and can cause some minor frontal plane lumbar spine architecture changes (structural or functional scoliosis…… if you want to drop such a heavy term on it).

Gait plays deeply into everything. Never underestimate any asymmetry in the body. Some part as to take up the slack or take the hit.

post link:

https://thegaitguys.tumblr.com/post/23230149195/we-could-have-easily-made-this-a-blog-post-about

Coordination of leg swing, thorax rotations, and pelvis rotations during gait: The organisation of total body angular momentum

"In walking faster than 3 km/h, transverse pelvic rotation lengthens the step (“pelvic step”).
The shift in pelvis–thorax coordination from in-phase to out of phase with increasing velocity was found to depend on the pelvis beginning to move in-phase with the femur, while the thorax continued to counter rotate with respect to the femur. "

We are always trying to bring greater understanding to this group at TGG regarding gait mechanics. One must understand the implications of rotational work, and anti-rotational work on the phasic and antiphasic nature of the thorax and the pelvis. We have talked about becoming more phasic when there is spine pain. With today's study, we delve just al little deeper, particularly noting how the pelvis and the femur moving together first, before that is offset by the antiphasic nature of the thorax at higher speeds of gait.
This article uses the terms in phase and out of phase. We have learned over time that those terms to relate more so the description of how the limbs are, or are not, pairing up when a couple is walking together. None the less, the reader here should understand how they are referring to out of phase as antiphasic.

http://www.sciencedirect.com/…/article/pii/S096663620700135X

Sagittal gait change in arthritic hips.

Asymmetries are the norm, whether they are anatomic or functional. This however does not mean that there may, or may not, be present or future consequences to the asymmetries.  It can take time for compensations to develop to accommodate these compensations, and it may take even further time for the body to present (and perhaps not present) consequences to the compensations.

In this study, progressing osteoarthritis in the hip began to eat away as some functional parameters that might otherwise have allowed for more symmetrical step and strike lengths, and one must not forget step width has to be in this discussion as well. 

"The patients walked significantly slower than the controls (p=0.002), revealed significantly reduced joint excursions of the hip (p<0.001) and knee (p=0.011), and a reduced hip flexion moment at midstance and peak hip extension (p<0.001). Differences were primarily manifested during the latter 50% of stance, and were persistent when controlling for velocity." - Eitzen et al.

Thus, to walk a straight line, some adaptive compensations will have to occur in the body to enable a linear progression. This might mean altering hip extension patterns, altering hip rotation relationships within the affected hip and thus of the contralateral hip (which might lead to pelvis distortion patterning), pelvis drift in the frontal plane, pelvis drift in the sagittal plane (APT, PPT), asymmetries in spinal rotation and thus arm swing, to name a few just regionally at the hip-pelvis-spine interval. Adaptations must be made. The question is, does your gait assessment afford you the insight to be addressing the problem, or merely their visible compensation, that is the hard part.  And remember what we always say, you gait analysis is only going to show you what your client is doing, not why they are doing it. Thus, fixing what you see is likely not fixing
"the why".

"Reduced gait velocity, reduced sagittal plane joint excursion, and a reduced hip flexion moment in the late stance phase of gait were found to be evident already in hip osteoarthritis patients with mild to moderate symptoms, not eligible for total hip replacement. " - Eitzen et al.

* Differences were primarily manifested during the latter 50% of stance, and were persistent when controlling for velocity.

https://www.ncbi.nlm.nih.gov/pubmed/23256709

BMC Musculoskelet Disord. 2012 Dec 20;13:258. doi: 10.1186/1471-2474-13-258.
Sagittal plane gait characteristics in hip osteoarthritis patients with mild to moderate symptoms compared to healthy controls: a cross-sectional study.
Eitzen I1, Fernandes L, Nordsletten L, Risberg MA.

Pod 133: Two Gait Cases & their Gait Rehab

Today we discuss a few cases we have seen.  We discuss 2 cases, both involved poorly adapted gaits from injury, adaptations that had become the client's new norm. Once you get past Ivo's case presentation, which is very in depth, the discussions quickly go into very important topics that we all over look, namely gait and gait rehab, gait thresholds, metabolic thresholds, cortical fatigue, and how to use some neurologic principles to restore a problematic gait.

Key Tag words:
gait, concussion, head trauma, cortical fatigue, endurance, strength, gait analysis, gait problems, gait rehab, running, running injuries, run-walk, SCFE, slipped epiphysis, femoral growth plate, hip stress fractures, growth plate injury, hip dysplasia, limping gait, club foot, step length, stride length

Links to find the podcast:

iTunes page: https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138?mt=2

http://traffic.libsyn.com/thegaitguys/pod_133final.mp3

http://thegaitguys.libsyn.com/pod-133-two-gait-cases-their-gait-rehab

Libsyn Directory: http://directory.libsyn.com/episode/index/id/6184651

Our Websites:
www.thegaitguys.com

summitchiroandrehab.com doctorallen.co shawnallen.net

Our website is all you need to remember. Everything you want, need and wish for is right there on the site.
Interested in our stuff ? Want to buy some of our lectures or our National Shoe Fit program? Click here (thegaitguys.com or thegaitguys.tumblr.com) and you will come to our websites. In the tabs, you will find tabs for STORE, SEMINARS, BOOK etc. We also lecture every 3rd Wednesday of the month on onlineCE.com. We have an extensive catalogued library of our courses there, you can take them any time for a nominal fee (~$20).

Our podcast is on iTunes and just about every other podcast harbor site, just google "the gait guys podcast", you will find us.

Medieval "Turn Shoes": How we used to walk.

In the 1500's in Western Europe, shoes were different. People wore “turn shoes”, leather shoes that were made inside out then reversed for wear. This was likely the beginning of the use of molds to make shoes, carpenters up until the twentieth century would carve a wooden foot model of various sizes to model the process and standardize it.

These "Turn Shoes" were replaced by shoes with a frame construction as shoes changed to adapt to different environments, as streets changed.

The Turn shoes were basically a slip on or lace up thick leather sock. Thus, they were zero drop, soft, and provided much "feel" for the ground. Proprioception was obviously well appreciated.

We have spoken about the difference between heel strike and heel contact in walking. One can safely heel strike if barefoot on soft grass, but one cannot on the hard concrete or asphalt that we have covered much of our world with. Thus, if one were to wear "turn shoes" in our modern era, one would be forced to adapt to a heel contact or "heel kiss" on the ground, meaning, a more predominant forefoot loading style as described in this video.

What he describes, is largely not a choice, it was because they were in soft thin leather sock all day long, and even on wood or hard dirt packed floors and cart paths all day long, the heels would want some reprieve from heel "strike".

Another way around this, to reduce heel strike, is to do it more naturally, by shortening the step and stride lengths a little, by keeping the body mass over the foot strike. "Chi Running" and "Chi walking" are based off of this principle. By moving the body mass forward with the foot, one has to naturally reduce heel strike. If one lags the body mass behind the foot however, the foot moves out in front, and heel strike begins to naturally (or shall we say, unnaturally) out in front, more heavily. This is not exactly desirable, for many reason.  Yet, since most of our shoes have some form of heel lift (a heel to forefoot drop), particular dress shoes (yes, even men's dress shoes, see photo), and even many modern day running shoes, the heel is essentially made more prominent (the heel rise essentially makes the brain think our heel (calcaneus) that much longer. This makes it easier, yet undesirable, to heel "strike" first. Oh what we have done for fashion !

He gets a few things wrong in the video, in terms of "ease" of walking, but largely it is decently done. One has to be careful if they perch the foot out in front like he does in the slower demonstration, in a plantarflexed ankle and foot, one can easily begin to lock up the knees. We often see this in teenagers in flip-flops.

-Shawn and Ivo, the gait guys

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Your gait and peripheral vision: Part 2. There is more to it than what you do/don’t see.

Written by Dr. Shawn Allen

Yesterday we did a blog post on the loss of peripheral vision from drooping eye lids leading to the necessity (not vanity based) of a minor surgical procedure called a blepharoplasty.  Here was that blog post (link), it had some important research based points you need to know.

Vision is typically the predominant sensory system used for guiding locomotion. Online visual control is critical for adjusting lower limb trajectory and ensuring proper foot placement, including optimal limb/foot crossing velocity, optimal trail-foot horizontal distance and lead-toe clearance. Research suggests that peripheral visual cues play a large role in this online gait control. 1

We have discussed many of these issues, the conscious and subconscious importance of vision on human gait, in many of our blog posts over time.  Namely, blog posts on dual-tasking attention, negotiating stairs, and even in tandem walking holding hands. These all require a degree of peripheral vision function otherwise gait problems, including falls, rise on the risk list.

According to Timmis and Buckley (2), “although gaze during adaptive gait involving obstacle crossing is typically directed two or more steps ahead, visual information of the swinging lower-limb and its relative position in the environment (termed visual exproprioception) is available in the lower visual field (lvf).”  Their study determined exactly when lvf exproprioceptive information is utilized to control/update lead-limb swing trajectory during obstacle negotiation. 

Their study determined that “when (the) lower visual field (lvf) was occluded, foot-placement distance and toe-clearance became significantly increased; which is consistent with previous work that likewise used continuous lvf occlusion”. Their findings suggest that “ lvf (exproprioceptive) input is typically used in an online manner to control/update final foot-placement, and that without such control, uncertainty regarding foot placement causes toe-clearance to be increased. Also that lvf input is not normally exploited in an online manner to update toe-clearance during crossing: which is contrary to what previous research has suggested.” 2

Elliot and Buckley (3) showed the importance of peripheral visual cues in the control of minimum-foot-clearance during overground locomotion. In their study, 

From their abstract: “eleven subjects walked at their natural speed whilst wearing goggles providing four different visual conditions: upper occlusion, lower occlusion, circumferential-peripheral occlusion and full vision. Results showed that under circumferential-peripheral occlusion, subjects were more cautious and increased minimum-foot-clearance and decreased walking speed and step length. The minimum-foot-clearance increase can be interpreted as a motor control strategy aiming to safely clear the ground when online visual exproprioceptive cues from the body are not available. The lack of minimum-foot-clearance increase in lower occlusion suggests that the view of a clear pathway from beyond two steps combined with visual exproprioception and optic flow in the upper field were adequate to guide gait. A suggested accompanying safety strategy of reducing the amount of variability of minimum-foot-clearance under circumferential-peripheral occlusion conditions was not found, likely due to the lack of online visual exproprioceptive cues provided by the peripheral visual field for fine-tuning foot trajectory.”

These appear to be important studies on the effects of vision and peripheral vision and proprioceptive cues.  How we move our bodies depends much on visual cues, the ones we know we see, and the ones we are unaware that we “see”. Take this to the next level, imagine how the blind must adapt to gait without these cues. That is gait topic we will save for another time.

So, the gait analysis you are doing with your runners, your athletes, your clients takes into consideration their vision right ? Hmmmm, some how we just know that many gait gurus just sat back in their chairs and let out a long exhale. We go even more rogue in podcast 95 when we discuss head tilt and the vestibular system, we know that one is almost always overlooked. Another long exhale we presume.

Shawn Allen … .  one of the gait guys

References:

1. Exerc Sport Sci Rev. 2008 Jul;36(3):145-51. doi: 10.1097/JES.0b013e31817bff72.Role of peripheral visual cues in online visual guidance of locomotion. Marigold DS¹.

2.Gait Posture. 2012 May;36(1):160-2. doi: 10.1016/j.gaitpost.2012.02.008. Epub 2012 Mar 17.Obstacle crossing during locomotion: visual exproprioceptive information is used in an online mode to update foot placement before the obstacle but not swing trajectory over it.Timmis MA¹, Buckley JG.

3. Gait Posture. 2009 Oct;30(3):370-4. doi: 10.1016/j.gaitpost.2009.06.011. Epub 2009 Jul 22.Peripheral visual cues affect minimum-foot-clearance during overground locomotion.Graci V¹, Elliott DB, Buckley JG.

Human gait is cyclical. For the most part, when one limb is engaged on the ground (stance phase), the other is in swing phase. Before we continue, you should recall that there is a brief double limb support phase in walking gait, that which is absent in running gait. Also, we wish to remind you of our time hammered principle that when the foot is on the ground the glutes are heavily in charge, and when the foot is in the air, the abdominals are heavily in charge.  

For us to move cleanly and efficiently one would assume that the best way to do that would be to ensure that the lower 2 limbs are capable of doing the exact same things, with the same timing, same skill, same endurance and same strength. This goes for the upper 2 limbs as well, and then of course the synchronizing of the 4 in a cohesive effort. For this clean seamless motor function to occur, one must assume that there would be no injuries that had left a remnant mark on one limb thus encouraging a necessary compensation pattern in that limb (and one that would then have to be negotiated with the opposite limb as well as the contralateral upper or lower limb).  For example, when right ankle rocker (dorsiflexion) is impaired, early heel departure will occur and hip extension will be limited. An alteration in right glute function will most likely follow.  One could theorize that the left step length (the length of measure from right heel strike through to left heel strike) would thus be shortened. This would cause a premature load onto the left limb, and could very well force the left frontal plane to be more engaged than is desirable. This could lead to left core and hip frontal plane weakness and compensation patterns to be generated (ie. right arm abduction. One can see all of these components in the photo above, and in this case here). It could also lead to a pelvic distortion pattern which would further throw off the anti-phasic nature of symmetrical and efficient gait.  To complicate the cyclical scenario, the time usually used to move sagittally will be partially used to move into, and back out of, the left frontal plane. This will necessitate some abbreviations in the left stance phase timely mechanical events. Some biomechanical events will have to be abbreviated or sped through and then the right limb will have to adapt to those changes. These are simple gait problems we have talked about over and over again here on the gait guys blog. (Search “arm swing” on our blog and you will find 45 articles around this topic.) These compensation patterns will include expressed weaknesses in various parts of the human frame as part of the pattern, and merely fixing those weaknesses does not address the right ankle rocker problem. Fixing said weaknesses merely encourages the brain to possibly continue to perpetuate necessary tightnesses in other muscles and engrain the compensations (challenges to mobility and stability) further or more complexly.  It is easy to find something weak, it takes a sharp brain to find the sometimes silent sparking event. Are you able to find the problem in this never ending loop of compensations and find a way to unwrinkle the system one logical piece at a time, or will you just chose to strengthen the wrinkled system and hope that the new strength on top of the compensations is adequate for you our your client ? One should not be forever sentenced to daily or weekly rehabilitative sessions/ homework to negate and alleviate symptoms, this is a far more durable machine than that. Fix the problem.

Now, lets add another wrinkle to the system.  What if there were problems before any injuries ?  Meaning, what if there were problems during the timely maturation and suppression of the primitive reflexes ? Or problems in the timely appearance or maturation of postural reflexes? A problem in these areas may very well result in a central or peripheral nervous system malfunction and a representation of such in one’s movement and gait.  That is a larger discussion for another time.

There is a reason that in our practices we often assess and treat contralateral upper and lower limbs as well as to address remnants from old injuries whether they are symptomatic or not. This is a really tough puzzle and game you are playing. For example, when there is insufficient hip internal rotation unilaterally you can regain some of the loss through increased foot pronation unilaterally, but at a consequence to both the local and global pictures.  Remember, most of the time you are trying to walk in a straight line from A to B and if the parts are not symmetrical you have many options to compensate. It is not as simple as telling your athlete to swing one arm more, or to stop pulling it across their body; they need to do those things, it is called a “compensation”. It is often not as simple as finding an impaired Rolling Pattern and driving it back to symmetry, in doing so, you may have just added strength and skill to a compensation.  Merely addressing things locally can be a crime.  If you are seeing an arm swing change, you would be foolish not to look at the opposite lower limb and foot at the very least, and of course assess spinal rotation, lateral flexion and hinging as well as core mobility and stability.  For your neuro nerds, remember the receptors from the central spine and core fire into the midline vermis of the cerebellum (one of the oldest parts of our brain, called the paleo cerebellum); and these pathways, along with other cerebellar efferents, fire our axial extensor muscles that keep us upright in the gravitational plane and provide balance or homeostasis.  So, those need assessed and addressed as well.  

Or, if this is too much thinking for you, … you can just train harder and get stronger . .  . in all your compensation patterns, after all, it is easier than figuring out why and how that right ankle started the whole mess, if in fact that is even the first piece of the puzzle.

Welcome to the matrix.

shawn and ivo, the gait guys

What Does Changing your Stride Cost You?

http://running.competitor.com/2013/09/training/study-changing-running-stride-does-more-harm-than-good_41136

A recent study cited in Competitor Magazine, talked about common stride “improvements” actually may reduce running economy. They looked at stride rate (cadence) and vertical displacement. One would think, with all the hoopla out there, that more steps per minute and less vertical displacement would be more efficient. The actual study concluded “Alterations led to an increase in metabolic cost in most cases, measured as VO2 uptake per minute and kg body mass,” Another study which had similar results can be found here.

Even though the study had a small sample size (16 participants), If you think about this, it makes sense.   Volitional effort usually has a metabolic cost. It does not make it right or wrong; they are just the facts. The nervous system will take time to integrate new (motor) patterns. Each person has a optimal (homestatic) stride “style” which includes vertical displacement as well as stride length, among other factors (lateral sway, ankle dorsi pantar flexion, knee flexion, thigh flexion, etc).

The study itself also concluded ““Mid- and long-term effects of altering … technique should also be studied.” we concur, we have not seen any long term studies that look at economy over time, but would love to read them if any of our readers run across them.

The Gait Guys.  Bringing you the facts without the bling.

Slow Your Gait & Shorten Your Stride and Your Brain May Slow

Slow Your Gait & Shorten Your Stride and Your Brain May Slow

Well, you have heard it here before, the receptors drive the brain, and here is another study that backs this up. Remember that receptors, which include not only joint mechanoreceptors, but also muscle mechanoreceptors (muscle spindles and golgi tendon organs) and tactile receptors in the skin (Merkels discs, paccinian corpuscles, etc) feed into the brain cortex (via the dorsal column system) and the cerebellum (via the spino cerebellar system). This afferent (sensory information) input is important for proper coordination as well as cognition and learning.

Remember, your brain is always remodeling. Here, the old adage “if you don’t use it, you will lose it” applies. More input = more synapses = more neuronal growth. So less motion = less input=synaptic atrophy = fewer connections and thus slower brain function.

Increased speed and length of stride stretches receptors more; decreased speed and shorter stride lengths decrease receptor activation. So, take big steps quickly, or you may turn into a zombie ! There is a reason why they walk slowly !

In July 2012 at the Alzheimer’s Association International Conference in Vancouver, British Columbia Mayo Clinic researchers presented research indicating that walking problems such as a slow gait and short stride are associated with an increased risk of cognitive decline. Computer assessed gait parameters (stride length, cadence and velocity) in study participants at two or more visits roughly 15 months apart. They revealed that participants with lower cadence, velocity and length of stride experienced significantly larger declines in global cognition, memory and executive function.

references:

http://www.aansneurosurgeon.org/2012/08/02/slow-gait-short-stride-linked-to-increased-risk-of-cognitive-decline/

http://www.newswise.com/articles/view/591437/?sc=dwhn

This week we will focus on the basics of gait and the gait cycle in our attempt to assist in gait literacy

Gait Cycle Basics: Part 1

Steps and strides….

What does the gait cycle that have to do with therapy or rehabilitation? Well, most people walk at some point in the day, and most have walked into your office. If people can’t carry the changes you made on the table and incorporate it into walking, then what you do will have limited effectiveness. Thus, the need for understanding the gait cycle as it relates to rehabilitation or how it can give you clues to the biomechanical faults present. An example is a loss of functional hip extension and chronic LBP/ SI dysfunction. This could be due to a myriad of reasons, from weak glutes, loss of ankle dorsiflexion, or even a dysfunctional shoulder. Understanding how these seemingly unrelated body parts integrate into the kinetic chain, especially while moving upright through the gravitational plane.

One gait cycle consists of the events from heel strike to heel strike on one side. A step length is the distance traveled from one heel strike to the next (on the opposite side). Comparing right to left step lengths can give the evaluator insight into the symmetry of the gait.  Differences in step length, on the simplest level, should cause the individual to deviate consistently from a straight line (technically it should cause the individual to eventually walk in a large circle!).  Often, compensations occur functionally in the lower kinetic chain to compensate for the differences in step length to ensure that you walk in a straight line.  It is these longstanding complex compensations that are the generators of many of our patient’s complaints.

A stride length is the distance from heel strike to heel strike on the ipsilateral side (the distance covered in one gait cycle.  Step width, or base of gait, is the lateral distance between the heel centers of two consecutive foot contacts (this typically measures 6-10 cm).  Foot progression angle is the angle of deviation of the long axis of the foot from the line of progression (typically 7-10 degrees). Çhanges in the progression angle can be due to both congenital (torsions, versions) as well as developmental reasons.

Next time we will take a closer look at the gait cycle itself. Yup, we are still…The Gait Guys

special thanks to Dr. Tom Michaud, who has allowed us to use these images in our book