An Alternate View of Crawling and Quadrupedal Motor Patterns: A Correlation to Free Solo Mountain Climbers ?

The one you haven’t heard about.

On janurary 15, 2014 Alex Honnold, Free-Soloed El Sendero Luminoso (The Shining Path) in El Potrero Chico, Mexico in a little over 3 hours. The climb rises 2500 feet to the summit of El Toro. At the time, it was considered to possibly be the most difficult rope-less climb in history, . . . until El Capitan.

Quadruped Patterns: Part 1, Redux
If you have been with us here at The Gait Guys for awhile, you will have read some articles where we discuss quadrupedal gait (link: Uner Tan Syndrome) and also heard us talk about CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs without sensory feedback. You will have also read many of our articles on arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during gait and running gaits.

Lets get into it, full blog post here,

https://www.thegaitguys.com/thedailyblog/an-alternate-view-of-crawling-and-quadrupedal

An Alternate View of Crawling and Quadrupedal Motor Patterns: A Correlation to Free Solo Mountain Climbers ?

Quadruped Patterns: Part 1

In the last 3 years, if you have been with us here at The Gait Guys that long, you will have read some articles where we discuss quadrupedal gait (link: Uner Tan Syndrome) and also heard us talk about CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs without sensory feedback. You will have also read many of our articles on arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during gait and running gaits. Through these articles, we have also eluded to some of the fruitless aspects of focusing solely on retraining arm swing in runners because of the deep neurologic interconnectedness to the lower limbs and to the CPG’s.
IF you are interested in any of these articles we have written please feel free to visit our blog and type in the appropriate words (Uner Tan Syndrome, arm swing, cerebellum, cross over gait) into the Search box on the blog.

Here we briefly look at interconnected arm and leg function in crawling mechanics in a high functioning human (as compared to the Uner Tan Syndrome) in arguably the best solo free climber in the world, Alex Honnold. Here we will talk about the possible neurologic differences in climbers such as Alex as compared to other quadruped species. Primarily, there is suspect of an existing shift in the central pattern generators because of the extraordinary demand on pseudo-quadrupedal gait of climbing because of the demand on the upper limbs and their motorneuron pools to mobilize the organism up the mountain. The interlimb coordination in climbing and crawling biomechanics shares similar features to other quadrupeds, both primate and non-primate, because of similarities in our central pattern generators (CPG’s). New research has however determined that the spaciotemportal patterns of spinal cord activity that helps to mediate and coordinate arm and leg function both centrally, and on a cord mediated level, significantly differ between the quadruped and bipedal gaits. In correlation to climbers such as Alex however, we need to keep it mind that the quadrupedal demands of a climber (vertical) vastly differ in some respects to those of a non-vertical quadrupedal gait such as in primates and those with Uner Tan Syndrome. This is obvious to the observer not only in the difference in quadrupedal “push-pull” that a climber uses and the center-of-mass (COM) differences. To be more specific, a climber keeps the COM within the 4 limbs and close to the same surface plane as the hands and feet (mountain) while a primate, human or Uner Tan person will “tent up” the pelvis and spine from the surface of contact.

What some of the research has determined is that in quadrupeds the lower limbs displayed reduced orientation yet increased ranges of kinematic coordination in alternative patterns such as diagonal and lateral coordination. This was clearly different to the typical kinematics that are employed in upright bipedal locomotion. Furthermore, in skilled mountain climbers, these lateral and diagonal patterns are clearly more developed than in study controls largely due to repeated challenges and subsequent adaptive changes to these lateral and diagonal patterns. What this seems to suggest is that there is a different demand and tax on the CPG’s and cord mediated neuromechanics moving from bipedal to quadrupedal locomotion. There seemed to be both advantages and disadvantages to both locomotion styles. Moving towards a more upright bipedal style of locomotion shows an increase in the lower spine (sacral motor pool) activity because of the increased and different demands on the musculature however at the potential cost to losing some of the skills and advantages of the lateral and diagonal quadrupedal skills. Naturally, different CPG reorganization is necessary moving towards bipedalism because of these different weight bearing demands on the lower limbs but also due to the change from weight bearing upper limbs to more mobile upper limbs free to not only optimize the speed of bipedalism but also to enable the function of carrying objects during locomotion.

The take home seems to suggest that gait retraining is necessary as is the development of proper early crawling and quadruped locomotor patterns. Both will tax different motor pools within the spine and thus different central pattern generators (CPG). A orchestration of both seems to possibly offer the highest rewards and thus not only should crawling be a part of rehab and training but so should forward, lateral and diagonal pattern quadrupedal movements, on varying inclines for optimal benefits. Certainly we need to do more work on this topic, the research is out there, but correlating the quad and bipedal is limited. We will keep you posted. Next week we will follow up on this quadrupedal topic with a video that will blow your mind ! So stay tuned !

Shawn and Ivo
The Gait Guys


Scand J Med Sci Sports. 2011 Oct;21(5):688-99. Idiosyncratic control of the center of mass in expert climbers. Zampagni ML, Brigadoi S, Schena F, Tosi P, Ivanenko YP.

J Neurophysiol. 2012 Jan;107(1):114-25. Features of hand-foot crawling behavior in human adults. Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F.

Gait and Climbing: Part 1

Lucid Dreaming is the name of a rock in the Buttermilks of Bishop, California. This is no ordinary rock. It is a V15. Summiting this rock is basically only 3 moves off of 3 holds, from your fingertips. The remainder of the climb is sliced bread. If you can do the 3, you can get to the top. The problem is, only a handful of people in the world can do it. How hard can this be, after all you start sitting down.

Strength, stability, mobility, endurance, skill, experience, movement patterns … . it is all here, today, on The Gait Guys blog.

Author: Dr. Shawn Allen

There are things that other people can do in life that rattle your brain. These are tasks that these individuals make look fairly simple, but in actuality are nearly impossible to the average person. The honest fact is that many of us could do many of these things to a degree if we would dedicate a portion of our day to building the engine to perform these tasks, but the truth is that many of us would rather sit down and be entertained than get up and struggle.

Here on The Gait Guys blog, bipedal and quadrupedal gait has been discussed for over 5 years. Discussions have gone deep into the strange quadrupedal gait of Uner Tan Syndrome and have delved into the critical neurology behind CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs. We have gone on and on about arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during walking running gaits.

Today I will look briefly at the interconnected arm and leg function in a high functioning human arguably one of the best new hot shots in climbing, Alex Megos. This year the German, as seen in this video link today, managed to summit Lucid Dreaming, a V15 in the Buttermilks of Bishop, California. Hell, you can say that this is just a big boulder, but there are not many V15s in the world like this one. Only a few of the very best in the world have even tried this rock, and you can count even fewer who have reached the summit. So, what does V15 mean to you? “virtually impossible” just about sums it up. Watch the video, this V15 starts from a “sit-start”, many folks wouldn’t even get their butts off the ground to complete the first move, that is how hard this is. Watch the video, if this does not cramp your brain, you perhaps you don’t have one.

Are there possible neurologic differences in climbers such as Megos as compared to other quadruped species? Primarily, there is suspect of an existing shift in the central pattern generators because of the extraordinary demand on pseudo-quadrupedal gait of climbing because of the demand on the upper limbs and their motorneuron pools to mobilize the organism up the mountain. We know these quadrupedal circuits exist. In 2005 Shapiro and Raichien wrote “the present work showed that human QL(quadrupedal locomotion) may spontaneously occur in humans with an unimpaired brain, probably using the ancestral locomotor networks for the diagonal sequence preserved for about the last 400 million years.”

As we all know, the interlimb coordination in climbing and crawling biomechanics shares similar features to other quadrupeds, both primate and non-primate, because of similarities in our central pattern generators (CPG’s). New research has however determined that the spaciotemportal patterns of spinal cord activity that helps to mediate and coordinate arm and leg function both centrally, and on a cord mediated level, significantly differ between the quadruped and bipedal gaits. In correlation to climbers such as Megos however, we need to keep in mind that the quadrupedal demands of a climber (vertical) vastly differ in some respects to those of a non-vertical quadrupedal gait such as in primates, in those with Uner Tan Syndrome and during our “bear crawl” challenges in our gyms. This should be obvious to the observer in the difference in quadrupedal “push-pull” that a climber uses and the center-of-mass (COM) differences. To be more specific, a climber must reduce fall risk by attempting to keep the COM within the 4 limbs while remaining close to the same surface plane as the hands and feet (mountain) while a primate, human or Uner Tan person will choose to “tent up” the pelvis and spine from the surface of contact which narrows the spreading of the 4 contact points. Naturally, this “tenting up” can be reduced, but the exercise becomes infinitely more difficult, to the point that most cannot quadrupedally ambulate more than a very short distance. I will discuss this concept in Part 2 of this series on climbing. If you study childhood development and crawling patterns, you need to be familiar with UTS (search our blog, save yourself the time), the flaws in the neurology behind the "Bird Dog” rehab pattern, and crawling mechanics … and of course, study climbers.

Some research has determined is that in quadrupeds the lower limbs displayed reduced orientation yet increased ranges of kinematic coordination in alternative patterns such as diagonal and lateral coordination. This was clearly different to the typical kinematics that are employed in upright bipedal locomotion. Furthermore, in skilled mountain climbers, these lateral and diagonal patterns are clearly more developed than in study controls largely due to repeated challenges and subsequent adaptive changes to these lateral and diagonal patterns. What this seems to suggest is that there is a different demand and tax on the CPG’s and cord mediated neuromechanics moving from bipedal to quadrupedal locomotion. There seemed to be both advantages and disadvantages to both locomotion styles. Moving towards a more upright bipedal style of locomotion shows an increase in the lower spine (sacral motor pool) activity because of the increased and different demands on the musculature however at the potential cost to losing some of the skills and advantages of the lateral and diagonal quadrupedal skills. Naturally, different CPG reorganization is necessary moving towards bipedalism because of these different weight bearing demands on the lower limbs but also due to the change from weight bearing upper limbs to more mobile upper limbs free to not only optimize the speed of bipedalism but also to enable the function of carrying objects during locomotion.

The take home seems to suggest that gait retraining is necessary as is the development of proper early crawling and progressive quadruped locomotor patterns. Both will tax different motor pools within the spine and thus different central pattern generators (CPG). A orchestration of both seems to possibly offer the highest rewards and thus not only should crawling be a part of rehab and training but so should forward, lateral and diagonal pattern quadrupedal movements, on varying inclines for optimal benefits. Certainly I need to do more work on this topic, the research is out there, but correlating the quad and bipedal is limited. I will keep you posted. Be sure to read my 3 part series on Uner Tan Syndrome, here on The Gait Guys blog. Some of today’s blog is rehash of my older writings, naturally I am setting the stage for “Part 2″ of Climbing.

- Dr. Shawn Allen

References:

Shapiro L. J., Raichien D. A. (2005). Lateral sequence walking in infant papio cynocephalus: implications for the evolution of diagonal sequence walking in primates. Am. J. Phys. Anthropol.126, 205–213 10.1002/ajpa.20049

Scand J Med Sci Sports. 2011 Oct;21(5):688-99. Idiosyncratic control of the center of mass in expert climbers. Zampagni ML , Brigadoi S, Schena F, Tosi P, Ivanenko YP

J Neurophysiol. 2012 Jan;107(1):114-25. Features of hand-foot crawling behavior in human adults. Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F.

Gait and Climbing: Part 1

Lucid Dreaming is the name of a rock in the Buttermilks of Bishop, California. This is no ordinary rock. It is a V15. Summiting this rock is basically only 3 moves off of 3 holds, from your fingertips. The remainder of the climb is sliced bread. If you can do the 3, you can get to the top. The problem is, only a handful of people in the world can do it. How hard can this be, after all you start sitting down.

Strength, stability, mobility, endurance, skill, experience, movement patterns … . it is all here, today, on The Gait Guys blog.

Author: Dr. Shawn Allen

There are things that other people can do in life that rattle your brain. These are tasks that these individuals make look fairly simple, but in actuality are nearly impossible to the average person.  The honest fact is that many of us could do many of these things to a degree if we would dedicate a portion of our day to building the engine to perform these tasks, but the truth is that many of us would rather sit down and be entertained than get up and struggle.

Here on The Gait Guys blog, bipedal and quadrupedal gait has been discussed for over 5 years. Discussions have gone deep into the strange quadrupedal gait of Uner Tan Syndrome and have delved into the critical neurology behind CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs. We have gone on and on about arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during walking running gaits.

Today I will look briefly at the interconnected arm and leg function in a high functioning human arguably one of the best new hot shots in climbing, Alex Megos. This year the German, as seen in this video link today, managed to summit Lucid Dreaming, a V15 in the Buttermilks of Bishop, California. Hell, you can say that this is just a big boulder, but there are not many V15s in the world like this one. Only a few of the very best in the world have even tried this rock, and you can count even fewer who have reached the summit. So, what does V15 mean to you? “virtually impossible” just about sums it up. Watch the video, this V15 starts from a “sit-start”, many folks wouldn’t even get their butts off the ground to complete the first move, that is how hard this is.  Watch the video, if this does not cramp your brain, you perhaps you don’t have one.

Are there possible neurologic differences in climbers such as Megos as compared to other quadruped species?  Primarily, there is suspect of an existing shift in the central pattern generators because of the extraordinary demand on pseudo-quadrupedal gait of climbing because of the demand on the upper limbs and their motorneuron pools to mobilize the organism up the mountain. We know these quadrupedal circuits exist. In 2005 Shapiro and Raichien wrote “the present work showed that human QL(quadrupedal locomotion) may spontaneously occur in humans with an unimpaired brain, probably using the ancestral locomotor networks for the diagonal sequence preserved for about the last 400 million years.”

As we all know, the interlimb coordination in climbing and crawling biomechanics shares similar features to other quadrupeds, both primate and non-primate, because of similarities in our central pattern generators (CPG’s). New research has however determined that the spaciotemportal patterns of spinal cord activity that helps to mediate and coordinate arm and leg function both centrally, and on a cord mediated level, significantly differ between the quadruped and bipedal gaits. In correlation to climbers such as Megos however, we need to keep in mind that the quadrupedal demands of a climber (vertical) vastly differ in some respects to those of a non-vertical quadrupedal gait such as in primates, in those with Uner Tan Syndrome and during our “bear crawl” challenges in our gyms. This should be obvious to the observer in the difference in quadrupedal “push-pull” that a climber uses and the center-of-mass (COM) differences.  To be more specific, a climber must reduce fall risk by attempting to keep the COM within the 4 limbs while remaining close to the same surface plane as the hands and feet (mountain) while a primate,  human or Uner Tan person will choose  to “tent up” the pelvis and spine from the surface of contact which narrows the spreading of the 4 contact points. Naturally, this “tenting up” can be reduced, but the exercise becomes infinitely more difficult, to the point that most cannot quadrupedally ambulate more than a very short distance. I will discuss this concept in Part 2 of this series on climbing.  If you study childhood development and crawling patterns, you need to be familiar with UTS (search our blog, save yourself the time), the flaws in the neurology behind the "Bird Dog” rehab pattern, and crawling mechanics … and of course, study climbers.

Some research has determined is that in quadrupeds the lower limbs displayed reduced orientation yet increased ranges of kinematic coordination in alternative patterns such as diagonal and lateral coordination.  This was clearly different to the typical kinematics that are employed in upright bipedal locomotion. Furthermore, in skilled mountain climbers, these lateral and diagonal patterns are clearly more developed than in study controls largely due to repeated challenges and subsequent adaptive changes to these lateral and diagonal patterns.  What this seems to suggest is that there is a different demand and tax on the CPG’s and cord mediated neuromechanics moving from bipedal to quadrupedal locomotion. There seemed to be both advantages and disadvantages to both locomotion styles. Moving towards a more upright bipedal style of locomotion shows an increase in the lower spine (sacral motor pool) activity because of the increased and different demands on the musculature however at the potential cost to losing some of the skills and advantages of the lateral and diagonal quadrupedal skills.  Naturally, different CPG reorganization is necessary moving towards bipedalism because of these different weight bearing demands on the lower limbs but also due to the change from weight bearing upper limbs to more mobile upper limbs free to not only optimize the speed of bipedalism but also to enable the function of carrying objects during locomotion.

The take home seems to suggest that gait retraining is necessary as is the development of proper early crawling and progressive quadruped locomotor patterns. Both will tax different motor pools within the spine and thus different central pattern generators (CPG). A orchestration of both seems to possibly offer the highest rewards and thus not only should crawling be a part of rehab and training but so should forward, lateral and diagonal pattern quadrupedal movements, on varying inclines for optimal benefits.  Certainly I need to do more work on this topic, the research is out there, but correlating the quad and bipedal is limited. I will keep you posted. Be sure to read my 3 part series on Uner Tan Syndrome, here on The Gait Guys blog. Some of today’s blog is rehash of my older writings, naturally I am setting the stage for “Part 2″ of Climbing.

- Dr. Shawn Allen

 References:

Shapiro L. J., Raichien D. A. (2005). Lateral sequence walking in infant papio cynocephalus: implications for the evolution of diagonal sequence walking in primates. Am. J. Phys. Anthropol.126, 205–213 10.1002/ajpa.20049

Scand J Med Sci Sports. 2011 Oct;21(5):688-99. Idiosyncratic control of the center of mass in expert climbers. Zampagni ML , Brigadoi SSchena FTosi PIvanenko YP

J Neurophysiol. 2012 Jan;107(1):114-25. Features of hand-foot crawling behavior in human adults. Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F.

Podcast 38: Usain Bolt, Arm Swing, Ballasts, & Running "Stuff"

Our show notes should interest you today. We have another great podcast ready for you !

Link to our server:

 http://thegaitguys.libsyn.com/podcast-38-usain-bolt-arm-swing-ballasts-running-stuff

iTunes link:

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

Gait Guys online /download store (National Shoe Fit Certification and more !) :

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:

2. Running and walking gadget:
Mashable (@mashable)
9/10/13 4:53 AM
This Clip-On Device Lets You Read Your Tablet While You Runon.mash.to/1akqMaK
4. Arm Swing:
- The Ballast Theory 
5. Off the web: Children’s Shoes
6. Off the MEdical Journal:
7.  Clinical Case Questions from a Reader:
Hello there, I’ve been following your stuff for a while now after searching far and wide for solutions to issues I have with my feet/ankles … . .
Chris 
8. Topic: Bartold on heelstrike
9. From the Medical Journal:
Neuroscientist. 2004 Aug;10(4):347-61.
Regulation of arm and leg movement during human locomotion.

Zehr EPDuysens J.

Rehabilitation Neuroscience Laboratory, University of Victoria, BC, Canada. pzehr@uvic.ca

Abstract: Walking can be a very automated process, and it is likely that central pattern generators (CPGs) play a role in the coordination of the limbs. Recent evidence suggests that both the arms and legs are regulated by CPGs and that sensory feedback also regulates the CPG activity and assists in mediating interlimb coordination. Although the strength of coupling between the legs is stronger than that between the arms, arm and leg movements are similarly regulated by CPG activity and sensory feedback (e.g., reflex control) during locomotion

10. Off pubmed: 
J Am Podiatr Med Assoc. 2012 Sep-Oct;102(5):390-5.

Anatomical origin of forefoot varus malalignment.

Lufler RSHoagland TMNiu JGross KD.
Forefoot varus malalignment is clinically defined as a nonweightbearing inversion of the metatarsal heads relative to a vertical bisection of the calcaneus in subtalar joint neutral. Although often targeted for treatment with foot orthoses, the etiology of forefoot varus malalignment has been debated and may involve an unalterable bony torsion of the talus. There was no association between forefoot alignment and talar torsion (r = 0.18; 95% confidence interval, -0.11 to 0.44; P = .22).These findings may have implications for the treatment of forefoot varus since they suggest that the source of forefoot varus malalignment may be found in an alterable soft-tissue deformity rather than in an unalterable bony torsion of the talus.

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 is a recycle article from our “The Gait Guys” blog archive, June 2011. This article focuses on altered proprioception. Proprioception (or kinesthesis) is our ability to orient our body or a body part in space.  Poor proprioception can result in balance and coordination difficulties as well as being a risk factor for injury. Think about people with syphillis who lose all afferent information from a joint coming in through the dorsal root ganglia, this ultimately leads to a wide based ataxic gait (due to a loss of position and tactile sense) and joint destruction (due to loss of position sense and lack of pain perception). The same consequences can occur, albeit on a smaller scale, when we have diminished proprioception from a joint or its associated muscle spindles. As you read on, keep the thought in your mind that walking or running are both actually repeated attempts at finding a stable single leg stance, one after the other. Impairment of one single leg stance will affect the involved side locally as well as the contralateral side due to accelerated or abbreviated loading responses coming off of the affected side.  Arm swing will also be altered and require compensation.

Proprioception is subserved by both cutaneous receptors in the skin (pacinian coprpuscles, Ruffini endings, etc.), joint mechanoreceptors (types I,II,III and IV) and from muscle spindles (nuclear bag and nuclear chain fibers) . It is both conscious and unconscious and travels in two pathways in the nervous system. 

Conscious proprioception arises from the peripheral mechanoreceptors in the skin and joints and travels in the dorsal column system to ultimately end in the thalamus, where the information is relayed to the cortex and cerebellum.

Unconscious proprioception arises from joint mechanoreceptors and muscle spindles and travels in the spino-cerebellar pathways to end in the midline vermis and flocculonodular lobes of the cerebellum. This unconscious information is then relayed from the cerebellum to the red nucleus to the thalamus and back to the cortex, to get integrated with the conscious proprioceptive information and then central program generators (CPG’s). We have spoken about receptors more recently in the Gait Guys podcasts, #19 & 20 and CPG’s in our previous blog post this week if you care to delve more deeply into these topics.

Information from both systems (both separate and combined; the nervous system loves redundancy) is then sent down the spinal cord to effect some response in the periphery. As you can see, there is a constant feed back loop between the proprioceptors, the cerebellum and the cerebral cortex. This is what allow us to be balanced and coordinated in our movements and actions.

Chronic ankle instability is merely a more serious form of dysfunction on the continuum of ankle pathomechanics. It refers to subjects with both coronal and saggital plane stability problems due to altered proprioception. This results in a loss of fine motor coordination of the foot (ie foot intrinsics) and a recruitment of larger motor units about the joint (peroneus longus,  flexor and extensor digitorum longus, tibialis posterior and anterior, etc) . This is equivalent to writing a letter with a pencil taped to your wrist, rather than in your fingers. 

This study looked at plantar pressure changes (actually it measured the amount of deviation in forward/backward and side to side motions, which are corrective motions by the CNS due to a loss of fine motor control). As expected, they were greater in the group with ankle instability, particularly when they led with that foot (ie the impaired foot). Thus they lacked the skill necessary to perform the task and developed another movement or recruitment pattern to compensate.

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 1st and you do not change the central pattern, you are carving a turnip with a chainsaw.

We are…. The Gait Guys

An Alternate View of Crawling and Quadrupedal Motor Patterns: A Correlation to Free Solo Mountain Climbers ?

Quadruped Patterns: Part 1

In the last 3 years, if you have been with us here at The Gait Guys that long, you will have read some articles where we discuss quadrupedal gait (link: Uner Tan Syndrome) and also heard us talk about CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs without sensory feedback. You will have also read many of our articles on arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during gait and running gaits. Through these articles, we have also eluded to some of the fruitless aspects of focusing solely on retraining arm swing in runners because of the deep neurologic interconnectedness to the lower limbs and to the CPG’s. 
IF you are interested in any of these articles we have written please feel free to visit our blog and type in the appropriate words (Uner Tan Syndrome, arm swing, cerebellum, cross over gait) into the Search box on the blog.

Here we briefly look at interconnected arm and leg function in crawling mechanics in a high functioning human (as compared to the Uner Tan Syndrome) in arguably the best solo free climber in the world, Alex Honnold. Here we will talk about the possible neurologic differences in climbers such as Alex as compared to other quadruped species. Primarily, there is suspect of an existing shift in the central pattern generators because of the extraordinary demand on pseudo-quadrupedal gait of climbing because of the demand on the upper limbs and their motorneuron pools to mobilize the organism up the mountain. The interlimb coordination in climbing and crawling biomechanics shares similar features to other quadrupeds, both primate and non-primate, because of similarities in our central pattern generators (CPG’s). New research has however determined that the spaciotemportal patterns of spinal cord activity that  helps to mediate and coordinate arm and leg function both centrally, and on a cord mediated level, significantly differ between the quadruped and bipedal gaits. In correlation to climbers such as Alex however, we need to keep it mind that the quadrupedal demands of a climber (vertical) vastly differ in some respects to those of a non-vertical quadrupedal gait such as in primates and those with Uner Tan Syndrome. This is obvious to the observer not only in the difference in quadrupedal “push-pull” that a climber uses and the center-of-mass (COM) differences.  To be more specific, a climber keeps the COM within the 4 limbs and close to the same surface plane as the hands and feet (mountain) while a primate,  human or Uner Tan person will “tent up” the pelvis and spine from the surface of contact.

What some of the research has determined is that in quadrupeds the lower limbs displayed reduced orientation yet increased ranges of kinematic coordination in alternative patterns such as diagonal and lateral coordination.  This was clearly different to the typical kinematics that are employed in upright bipedal locomotion. Furthermore, in skilled mountain climbers, these lateral and diagonal patterns are clearly more developed than in study controls largely due to repeated challenges and subsequent adaptive changes to these lateral and diagonal patterns.  What this seems to suggest is that there is a different demand and tax on the CPG’s and cord mediated neuromechanics moving from bipedal to quadrupedal locomotion. There seemed to be both advantages and disadvantages to both locomotion styles. Moving towards a more upright bipedal style of locomotion shows an increase in the lower spine (sacral motor pool) activity because of the increased and different demands on the musculature however at the potential cost to losing some of the skills and advantages of the lateral and diagonal quadrupedal skills.  Naturally, different CPG reorganization is necessary moving towards bipedalism because of these different weight bearing demands on the lower limbs but also due to the change from weight bearing upper limbs to more mobile upper limbs free to not only optimize the speed of bipedalism but also to enable the function of carrying objects during locomotion.

The take home seems to suggest that gait retraining is necessary as is the development of proper early crawling and quadruped locomotor patterns. Both will tax different motor pools within the spine and thus different central pattern generators (CPG). A orchestration of both seems to possibly offer the highest rewards and thus not only should crawling be a part of rehab and training but so should forward, lateral and diagonal pattern quadrupedal movements, on varying inclines for optimal benefits.  Certainly we need to do more work on this topic, the research is out there, but correlating the quad and bipedal is limited. We will keep you posted. Next week we will follow up on this quadrupedal topic with a video that will blow your mind ! So stay tuned !

Shawn and Ivo
The Gait Guys


Scand J Med Sci Sports. 2011 Oct;21(5):688-99. Idiosyncratic control of the center of mass in expert climbers. Zampagni ML, Brigadoi S, Schena F, Tosi P, Ivanenko YP.

J Neurophysiol. 2012 Jan;107(1):114-25. Features of hand-foot crawling behavior in human adults. Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F.