The unbalanced athlete, motor pattern, team, joint etc…… is not efficient.

Like him or not, believing he should have lost his last fight (or not), Georges St-Pierre was/is one of the best MMA fighters of all time. He was once quoted as saying, 

“In fighting, in evolution, in life, efficiency is the key,” says St-Pierre. 

 ”It’s not the most powerful animal that survives. It’s the most efficient.

This certainly describes most of Georges fights. There were always bigger, faster, meaner, stronger opponents. However, most of his fights went the distance. Eight of his last nine fights went to a five round decision. Now, there are those who will say that he didn’t have the finishing power or submission skills to close fights in the earlier rounds, and that is debatable for sure.  However, there is no doubt that anyone’s best fighting attributes will diminish as the rounds progress and fatigue sets in.  But, perhaps this is an equalizer when someone doesn’t have one single “golden right hand”, or what have you.  Efficiency can be the great equalizer.

St-Pierre isn’t your typical fighter. He’s arguably the best mixed martial artist in the world, a 5-foot 11-inch, 190-pound destroyer. Up until his most recent fight with Johnny Hendricks, he had not lost a round in more than 3 years, that is pure efficiency ! Arguably, he is faster than other fighters, he is more fit, has a greater range of skills, has better endurance …  in a Darwinian sense, perhaps more efficient ?

Here at the Gait Guys we are always considering efficiency.  As you can see from the slide above, there are many factors that can diminish efficiency.  We strive for as much symmetry as we can because with neuromuscular symmetry efficiency can be maximized.  Keep in mind however, that total symmetry is not always possible. Most people have two different feet, often one is more varus because it sat against the mothers rounded belly in utero.  And, one tibia is often more bowed or torsioned than the other for the same reason.  So, perfect symmetry is not always possible or guaranteed. But, one can do alot to gain as much physical symmetry as possible through detailed study of your client. (Remember, just because things look symmetrical does not mean that they function symmetrically ! This game is not that easy ! But, for some of the uneducated, it may seem to be !)  When physical symmetry is regained often the sensory-motor nervous system becomes functionally more symmetrical.  And, this is a flippable phenomenon, when neuro symmetry is driven often physical symmetry will be driven in time.  

Think about the afferent input to the cortex from the peripheral receptors in the skin (Paccinian corpuscles, Merkels discs, etc); the joint mechanorecpetors (types I-IV) and muscle receptors (spindles and Golgi tendon organs). Generally speaking, they travel up the dorsal columns on the back of the spinal cord to the thalamus and then the cortex; up the dorsal spinocerebelllar tract, to the cerebellar hemispheres; the spino- reticular tract to the reticular formation, or in the case of the upper cervical spine, directly into or flocculonodular lobe of the cerebellum. This information needs to be equal and opposite from each side of the extremity (flexors and extensors) as well as the right and left sides of the body. This “Balance” or “Homeostasis” or what the Chinese called Yin and Yang is key to efficiency.

In your workouts and rehab, strive for symmetry. We like to say “Tailor your exercises to the weaker side”. This helps to create more equality rather than a larger disparity.

The Gait Guys. Making it Real…Each Day….On the Blog…

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.

Though you weigh less when naked, it doesn’t mean you are more efficient…

“Running barefoot offers no metabolic advantage over running in lightweight, cushioned shoes.”

This study looked at VO2 max (ie. the bodies ability to utilize oxygen, or more precisely, the maximal oxygen uptake or the maximum volume of oxygen that can be utilized in one minute during maximal or exhaustive exercise. It is measured as milliliters of oxygen used in one minute per kilogram of body weight ).

The study found that VO2 increased as weight was added to the foot, whether or not ehy were wearing shoes AND there was not significant difference.

“V˙O(2) increased by approximately 1% for each 100 g added per foot, whether barefoot or shod (P < 0.001). However, barefoot and shod running did not significantly differ in V˙O(2) or metabolic power. A consequence of these two findings was that for footwear conditions of equal mass, shod running had ∼3%-4% lower V˙O(2) and metabolic power demand than barefoot running (P < 0.05).”

An interesting finding was that VO2 was actually 3-4% less for shod running than barefoot, indicating increased metabolic efficiency (albeit small) for shoes.

Why? Our theory is increased biomechanical efficiency with shoes. Shoes, creating less pronatory force and accessory motion (due to cushioning and constraints of the shoe; ie it takes some of the complexity out of the motion) created a more rigid lever with better force transduction.

The Gait Guys. Asking the hard questions and giving you the facts with each post.       


Med Sci Sports Exerc. 2012 Aug;44(8):1519-25. doi: 10.1249/MSS.0b013e3182514a88.

Metabolic cost of running barefoot versus shod: is lighter better?

Source

Locomotion Lab, Department of Integrative Physiology, University of Colorado, Boulder, CO, USA. jason.franz@colorado.edu

Abstract

PURPOSE:

Based on mass alone, one might intuit that running barefoot would exact a lower metabolic cost than running in shoes. Numerous studies have shown that adding mass to shoes increases submaximal oxygen uptake (V˙O(2)) by approximately 1% per 100 g per shoe. However, only two of the seven studies on the topic have found a statistically significant difference in V˙O(2) between barefoot and shod running. The lack of difference found in these studies suggests that factors other than shoe mass (e.g., barefoot running experience, foot strike pattern, shoe construction) may play important roles in determining the metabolic cost of barefoot versus shod running. Our goal was to quantify the metabolic effects of adding mass to the feet and compare oxygen uptake and metabolic power during barefoot versus shod running while controlling for barefoot running experience, foot strike pattern, and footwear.

METHODS:

Twelve males with substantial barefoot running experience ran at 3.35 m·s with a midfoot strike pattern on a motorized treadmill, both barefoot and in lightweight cushioned shoes (∼150 g per shoe). In additional trials, we attached small lead strips to each foot/shoe (∼150, ∼300, and ∼450 g). For each condition, we measured the subjects’ rates of oxygen consumption and carbon dioxide production and calculated metabolic power.

RESULTS:

V˙O(2) increased by approximately 1% for each 100 g added per foot, whether barefoot or shod (P < 0.001). However, barefoot and shod running did not significantly differ in V˙O(2) or metabolic power. A consequence of these two findings was that for footwear conditions of equal mass, shod running had ∼3%-4% lower V˙O(2) and metabolic power demand than barefoot running (P < 0.05).

CONCLUSIONS:

Running barefoot offers no metabolic advantage over running in lightweight, cushioned shoes.

PMID: 22367745
http://www.ncbi.nlm.nih.gov/pubmed/22367745

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

Barefoot Versus Running Shoes: Which Is (Surprisingly) More Efficient?

Many folks extol the virtues of barefoot or minimal running shoes and or styles. We have contended that you often need to “earn the right” to be able to do this through our mantra “skill, endurance, strength”.

Here is an interesting take by Alex Hutchinson from Runner World and his review of Franz, Wierzbinski and Kram’s study published in Medicine and Science in Sports and Exercise, explaining why, metabolically speaking, shod running may be more efficient

The Gait Guys: sifting and surfing so you don’t have to…

Barefoot Versus Running Shoes: Which Is (Surprisingly) More Efficient?