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Aside from the Robbins-Gouwe research, is there anything in the literature that examines consciously overriding the CNS-derived gait? Better yet, is there data that suggests injury rate increases the farther one deviates from the "optimal" gait? This is a topic that would be of interest to any running coach.
Another one to check out: Effect of a global alteration of running technique on kinematics and economy
Dallam GM, Wilber RL, Jadelis K, Fletcher G, Romanov N.
Journal of Sports Sciences
The Following User Says Thank You to Bobba Booey For This Useful Post:
Simon, you're a terrible teacher. ;-) I'll respond to the injury rate issue after reading the literature.
In the interim, here's some of the other answers:
Overstriding: average step length greater than the peak metabolic efficiency point.
Understriding" average step length shorter than the peak metabolic efficiency point.
Regarding the Robbins-Gouw studies: It seems to match my experiences, but recent experimentation with cushioned shoes introduces some new-found skepticism.
Regarding the CNS issue: The problem arises from new runners not relying exclusively on the sub-conscious to guide gait. They seem to mimic others (since you mentioned Rogers... think Bandera), which goes back to your question about the conscious overriding the sub-conscious. Simply explaining that their body will gravitate towards the metabolic ideal seems like it would be helpful in many cases.
I should note my own running form teaching methods rely heavily on "feeling", which is just a colloquial way to describe sub-conscious learning. I didn't ask the question to minimize the role of the sub-conscious. I was simply curious about your thoughts on the matter.
Overstriding: average step length greater than the peak metabolic efficiency point.
Understriding" average step length shorter than the peak metabolic efficiency point.
So does Usain Bolt over-stride then? He has a lower step frequency and cadence than his nearest rivals, but a much bigger stride length. Is this stride length metabolically efficient- doubtful. Do all sprinters "over-stride" then? They're faster in terms of miles / hour than distance runners....
So does Usain Bolt over-stride then? He has a lower step frequency and cadence than his nearest rivals, but a much bigger stride length. Is this stride length metabolically efficient- doubtful. Do all sprinters "over-stride" then? They're faster in terms of miles / hour than distance runners....
Based on my definition, we wouldn't know that without measuring his metabolic efficiency. Given his speed, it would be a fairly safe assumption he's operating at or very near his peak, thus he wouldn't be overstriding.
Regarding sprinters versus distance runners: Individuals will vary, but sprinters should have a longer stride length due to a greater velocity.
Based on my definition, we wouldn't know that without measuring his metabolic efficiency. Given his speed, it would be a fairly safe assumption he's operating at or very near his peak, thus he wouldn't be overstriding.
Regarding sprinters versus distance runners: Individuals will vary, but sprinters should have a longer stride length due to a greater velocity.
I'd say he'll be functioning anaerobically. And what influence does this have on metabolic cost?
So now you're saying that speed is important in "over-striding" not just the metabolic cost which is what you stated previously. So your definition has changed already.
I've pulled a couple of references and Bobba has added another which show that metabolic cost goes up when runners run outside their preferred step frequency, have you found any studies which demonstrate an increase in injury risk in association with fatigue yet?
I suspect you find me difficult as a teacher because I challenge you to learn for yourself and don't tell you how wonderful you aren't. Never mind, I know this teaching style doesn't suit all learners.
Regarding sprinters versus distance runners: Individuals will vary, but sprinters should have a longer stride length due to a greater velocity.
So, what you are saying is that if distance runners want to run at a higher velocity. i.e. faster, then they should have a longer stride length- right Jason?
Now, do runners generally take longer strides when they are barefoot or shod, in your experience Jason?
I should clarify- I don't necessarily advocate a shortened stride as a default... over-striding just appears to be more common than under-striding.
I agree with all of these points, which brings me to another question. Kevin, you mentioned earlier that most experienced runners will self-select the ideal stride length for any given condition. Based on my own personal experiences and observations, I agree. What about novice runners?
Even barefoot, where they have the added sensory input of plantar tactile sensation, many newer runners have a difficult time finding that metabolic efficiency sweet spot. Wouldn't these individuals likely benefit from some basic "how to run" instruction, or even a simple explanation of how the CNS regulates gait for maximum efficiency? For example, you mentioned you often teach runners to shorten their stride. Wouldn't this be beneficial if they are clearly striding outside their optimal metabolic efficiency zone?[/
My experience has been that novice runners tend to more commonly overstride than their more seasoned counterparts. I find that most of these individuals who overstride while running are adults who rarely participated in running type sports as a child or youth and, as a result, have not developed the proper motor skills necessary to know how to run most efficiently. I see overstriiding also at the high school level some but most good high school coaches spot this problem immediately and make the necessary adjustments to increase the stride frequency and decrease the stride length of their overstriding runners.
In order to demonstrate this to the runner in my office or in the running clinics I do, I will purposefully overstride and then understride running up and down the hallway. I tell the runner to observe the up and down excursions of my head between the two extremes of running and that it requires more energy and will cause more impact with the ground if they are moving their bodies up and down more with each running step. This generally enables them see the difference and also enables them to better understand the mechanical concepts involved in overstriding with more clarity. This has been something I have been teaching in my running biomechanics lectures and running clinic demonstrations for the past 28 years.
Again, I am not the first to suggest the importance of overstriding since, my cross country coach with the UC Davis Aggies was also a world renowned exercise physiologist, Dr. William C. Adams, who taught me, and the rest of the Aggies in that era, quite a bit about exercise physiology and good running biomechanics. My BS at UC Davis was in Animal Physiology and I also took three graduate level Exercise Physiology courses during my four years at UC Davis. I also participated as a research assistant and subject in a few running research projects at UC Davis as an undergraduate. I am attaching a photo of myself from one of the research projects I was a subject in where we were comparing heat regulation and sweat loss in male and female runners in hot-dry and warm-humid environments. I was 21 years old at the time (34 years ago).
As far as optimizing stride length and stride frequency and, therefore, discussing the concept of "over-striding" and "under-striding", we must be very careful that we are discussing what parameter we are optimizing for. In other words, are we more interested in optimizing stride length/stride frequency for metabolic efficiency (i.e. consuming the least amount of oxygen for a given running velocity), in optimizing stride length/stride frequency for injury prevention (i.e. placing the least stress on the structural components of the foot and lower extremity), or in optimizing stride length/stride frequency for pain reduction (i.e. running so that there is the least amount of pain with an existing running injury).
In general, the existing research tends to point to the fact that the central nervous system (CNS) tends to choose the most metabolically efficient stride length/stride frequency in experienced runners. However, the optimal stride length/stride frequency for minimizing metabolic energy expenditure may not be the same stride length/stride frequency that produces the fewest injuries or is the most comfortable stride length/stride frequency for a given running velocity. Therefore, if we are to move further in this discussion, let us please be clear what parameter we are optimizing for in our discussions of "over-striding" or "under-striding": metabolic efficiency, decreased stress or pain reduction.
Quote:
Originally Posted by Jason Robillard
It's a tangent, but I don't believe there is any research on the factors that would affect the time needed for the CNS to "regulate" gait to maximize efficiency. Based on your personal experiences as a runner and observer of runners, have you noticed any patterns that could be used to predict the length of time this regulation takes?
Obviously, runners should all be able to change their stride parameters to some extent, but some runners will probably be better able than others at making these changes. In this regard, Irene Davis, PhD, (who I will be debating a few weeks on "barefoot vs shod running" at the annual ACSM meeting in San Francisco) is now doing some very interesting research on gait retraining in runners.
Irene straps accelerometers to the lower legs of runners with an instant auditory feedback to the runners on a treadmill that allows the runners to have a real-time feedback as to how best to alter their running kinematics to minimize tibial acceleration. She claims that she can retrain runners very effectively with about six 30 minute sessions on the treadmill (if my memory serves me correctly). I would suspect that this would be the minimum needed for most experienced runners who have been running with a certain pattern of running gait kinematics for years.
Of course, running with a kinematic pattern that minimizes tibial acceleration may reduce some types of running injuries, but may also not be the most metabolically efficient way to run, may not optimize for preventing other types of injuries and may not be the most comfortable way to run for all runners. However, Irene's groundbreaking research is certainly on the cutting edge of what we may all be looking more closely at in the future if it is found that this type of gait retraining does reduce the frequency of certain running injuries, is more metabolically efficient and is a running pattern that the runner can continue to "remember" for a long period of time after the gait retraining sessions have been completed.
Good discussion, Jason.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Interestingly, I had this very discussion with a trail runner utilizing the Pose method in a recent ultramarathon. The runner had a great deal of excessive movement given the incredibly slow pace and was clearly wasting energy. They did not appreciate my advice.
Aside from the Robbins-Gouwe research, is there anything in the literature that examines consciously overriding the CNS-derived gait? Better yet, is there data that suggests injury rate increases the farther one deviates from the "optimal" gait? This is a topic that would be of interest to any running coach.
Jason:
I have seen the same problems with the Pose method runners where they seem to be "tip-toeing" when they run, more concerned with proper foot strike placement than with being efficient and getting from point A to point B with a more reasonable amount of running efficiency and speed. In fact, Nick Romanov was part of this study that showed the Pose running was 7.6% less metabolically efficient than the self-selected running style chosen by 16 sub-elite triathletes who were trained on Pose running over a 12 week period (Dallam GM, Wilber RL, Jadelis K, Fletcher GJ, Romanov N: Effect of a global alteration of running technique on kinematics and economy. J Sports Sciences, 23:757-764, 2005.) Certainly this study, where Romanov was involved with the study himself and showed signficantly reduced metabolic efficiency with his "Pose" running technique, isn't a glowing recommendation for altering stride length/stride frequency to his technique.
Again, as I mentioned in my last posting, the optimal running gait pattern for increasing metabolic efficiency may not be also the optimal running gait pattern for minimizing injury risk. There is no research to my knowledge that examines this subject. One reason this type of research has not been done is that trying to determine the optimal gait pattern to minimize injury risk would be an exceedingly difficult study to do since we would be attempting to override the central nervous system (CNS) control patterns with new running styles that would require conscious thought, concentration and an extended training period and an even more extended observation period to do so. I don't think many runners would be too anxious to volunteer for this type of research.
I do think, however, that a good running coach can help many runners achieve a more metabolically efficient running style that should reduce injury risk. The problem is that unless the individual coaching running form is very knowledgeable of running biomechanics and exercise physiology, and unless they are willing to accept the fact that each individual may have their own specific footstrike pattern (i.e. heel-strike, midfoot strike or forefoot strike) to achieve this optimal running form, they may be doing more harm than good for the runner.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Again, as I mentioned in my last posting, the optimal running gait pattern for increasing metabolic efficiency may not be also the optimal running gait pattern for minimizing injury risk. There is no research to my knowledge that examines this subject.
Yet we can use logical reasoning here: fatigue has been shown to be a predictor for running related injuries; a less metabolically efficient running style should lead to greater fatigue than a more metabolically efficient running style; altering stride kinematics from the preferred, sub-conciously adopted running style results in decreased metabolic efficiency and should therefore result in higher levels of fatigue; thus it might be reasoned that consciously attempting to alter stride kinematics increases the risk of injury by increasing fatigue.
Now, since fatigue is not the only predictor of running related injuries and other factors come into play too, then the increased injury risk due to fatigue might be off-set by change in another risk factor resulting from the change in stride kinematics. But it might not too.
evening all,
engaging debate as ever. I've read most of this thread (there is rather a lot to get through but i'm enjoying it). I didnt see this mentioned. it might be on another thread. More stuff from Daniel Leiberman (with a gift from Vibrams!)
Anyone any thoughts on it? I have the PDF but not sure if i'm allowed to put it on.
Foot Strike and Injury Rates in Endurance Runners:
A Retrospective Study
Adam I. Daoud1, Gary J. Geissler2, Frank Wang3, Jason Saretsky2,
Yahya A. Daoud4, and Daniel E. Lieberman1
evening all,
engaging debate as ever. I've read most of this thread (there is rather a lot to get through but i'm enjoying it). I didnt see this mentioned. it might be on another thread. More stuff from Daniel Leiberman (with a gift from Vibrams!)
Anyone any thoughts on it? I have the PDF but not sure if i'm allowed to put it on.
Foot Strike and Injury Rates in Endurance Runners:
A Retrospective Study
Adam I. Daoud1, Gary J. Geissler2, Frank Wang3, Jason Saretsky2,
Yahya A. Daoud4, and Daniel E. Lieberman1
Certainly this study, where Romanov was involved with the study himself and showed signficantly reduced metabolic efficiency with his "Pose" running technique, isn't a glowing recommendation for altering stride length/stride frequency to his technique.
It was amusing to read Dr. Romanov's response to the conclusion of less efficiency, see here. He makes the statement, "Do we really need to be so much concerned about economy?" He even quoted Tim Noakes to somehow add validity to his statement because we don't yet understand all the factors that affect running economy.
If that wasn't enough misuse of the science, there is also this study:
Reduced eccentric loading of the knee with the pose running method
Arendse RE, Noakes TD, Azevedo LB, Romanov N, Schwellnus MP, Fletcher G.
Medicine & Science in Sports & Exercise: Volume 36(2) February 2004 pp 272-277
Dr. Ross Tucker and Dr. Jonathan Dugas, have an nice analysis on this study found here. Dr. Romanov and his team touted this study as proof of the benefits of Pose. What they didn't publish is that "of the twenty runners who were trained, more than half broke down with calf muscle injury, Achilles tendon strains and other injuries of the feet."
Something that has already been stated many times on the Arena and was also stated by Tucker and Dugas in regards to changing running form, "eccentric loading doesn't just disappear, it goes somewhere else."
The Following User Says Thank You to Bobba Booey For This Useful Post:
I also can't speak for Simon, but assume his comments are motivated by all the nonsensical one liner posts we have had here from barefoot runners over the years who never come back to engage or never answer the questions they get asked or straight out lie about the research or ...
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Still here, but relegated to reading the conversation on my phone. I'll comment as soon as I get more regular internet access.
One comment, though- if you exclude the militant barefoot runners, there's far more agreement than disagreement between the barefoot and podiatry community on most of these issues.
One comment, though- if you exclude the militant barefoot runners, there's far more agreement than disagreement between the barefoot and podiatry community on most of these issues.
Jason:
Looking forward to your continued discussions with us. Our little chat, so far, has probably been helpful for both sides of the barefoot vs shod running discussion.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
It was amusing to read Dr. Romanov's response to the conclusion of less efficiency, see here. He makes the statement, "Do we really need to be so much concerned about economy?" He even quoted Tim Noakes to somehow add validity to his statement because we don't yet understand all the factors that affect running economy.
If that wasn't enough misuse of the science, there is also this study:
Reduced eccentric loading of the knee with the pose running method
Arendse RE, Noakes TD, Azevedo LB, Romanov N, Schwellnus MP, Fletcher G.
Medicine & Science in Sports & Exercise: Volume 36(2) February 2004 pp 272-277
Dr. Ross Tucker and Dr. Jonathan Dugas, have an nice analysis on this study found here. Dr. Romanov and his team touted this study as proof of the benefits of Pose. What they didn't publish is that "of the twenty runners who were trained, more than half broke down with calf muscle injury, Achilles tendon strains and other injuries of the feet."
Something that has already been stated many times on the Arena and was also stated by Tucker and Dugas in regards to changing running form, "eccentric loading doesn't just disappear, it goes somewhere else."
Has anyone else noticed that its the Pose coaches or those touting the Pose approach are the most sensitive to criticism?
Why do they go to such extraordinary lengths to dismiss any study that does not support Pose running yet blindly accept any study that does?
__________________ Craig Payne
__________________________________________________ ___________________________________ Follow me on Twitter | Run Junkie God put me on this earth to accomplish a certain number of things - right now I am so far behind, I will never die.
I wrote an article on this subject last year and posted it on my blog "XXXXXXXXXXX" and the "Barefoot Runners of XXXXXXX" attacked me and, quite frankly, scared me. I was deluged with hate mail and was so shaken up that I took the article down. My impression was they are unhappy people who enjoy anonymous bullying of anybody with a differing opinion.
Why do they do that for?. Why are they so incapable of addressing and discussing the issues that they have to resort to hateful anonymous crap for?
You know you have got it right when all they have left is to resort to such ad hominem attacks
Podiatrist Paul Langer used to see one or two barefoot running injuries a month at his Twin Cities Orthopedics practice in Minneapolis. Now he treats between three and four a week.
Swept by the barefoot running craze, ultramarathoner Ryan Carter ditched his sneakers for footwear that mimics the experience of striding unshod.
The first time he tried it two years ago, he ran a third of a mile on grass. Within three weeks of switching over, he was clocking six miles on the road.
During a training run with a friend along a picturesque bike path near downtown Minneapolis, Carter suddenly stopped, unable to take another step. His right foot seared in pain.
"It was as though someone had taken a hammer and hit me with it," he recalled.
Carter convinced his friend to run on without him. He hobbled home and rested his foot. When the throbbing became unbearable days later, he went to the doctor. The diagnosis: a stress fracture.
Hmmm... it would seem some element of transitioning did occur in this case i.e. by 3 weeks was running close to 10km (6miles) whilst starting off with 500-600m (1/3 of a mile) initially. Obviously this wasn't enough for this individual. When I ran in my new Vibram Classics (back in 2007) I did 15km straight up on a combination of grass/dirt terrain. Yes, us humans are not all the same for various reasons (physiology, biomechanics... & also general health... & also diet/nutrition!) thus various outcomes will ensue - but we've all been down this path before.
Quote:
Bob Baravarian, chief of podiatry at the UCLA Medical Center in Santa Monica, Calif., said he's seen "a fair number" of heel injuries and stress fractures among first-timers who are not used to the different forces of a forefoot strike.
"All of a sudden, the strain going through your foot is multiplied manifold" and problems occur when people don't ease into it, he said.
Running injuries are quite common. Between 30 to 70 percent of runners suffer from repetitive stress injuries every year and experts can't agree on how to prevent them. Some runners with chronic problems have seized on barefoot running as an antidote, claiming it's more natural. Others have gone so far as to demonize sneakers for their injuries.
... & I'm not going to comment further on that "Pre-human ancestors" B.S... is there any wonder why there is so much confusion on this topic (& others) when there is such moronic reasoning being touted around... as if it was fact! As I've said before... stick to the empirical science (i.e. observational, experimental) & greater enlightenment may ensue.
And just think of it...the first suggestion of correlation between Vibram FiveFingers and metatarsal stress fractures occurred here on Podiatry Arena over two years ago on May 5, 2010 in the thread Vibram FiveFingers Cause Metatarsal Stress Fractures?!!
Podiatry Arena leads the way!!
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
I don't get involved in these blogs often, but I must respectfully disagree with you. I have been involved in a number of debates and they have been very healthy.
I also want to caution you against making statements about injuries. If every sports med doc wrote a case series on shod runners with metatarsal stress fractures, for example, the literature would be flooded. These are some of the most common injuries in shod runners - as is achilles tendinitis! Shod runners get injured at a rate of up to 79%/yr. We do not know how barefoot compares at this moment - but I can tell you that we will soon. Lets all wait to see what the data say.
I don't get involved in these blogs often, but I must respectfully disagree with you. I have been involved in a number of debates and they have been very healthy.
I also want to caution you against making statements about injuries. If every sports med doc wrote a case series on shod runners with metatarsal stress fractures, for example, the literature would be flooded. These are some of the most common injuries in shod runners - as is achilles tendinitis! Shod runners get injured at a rate of up to 79%/yr. We do not know how barefoot compares at this moment - but I can tell you that we will soon. Lets all wait to see what the data say.
Hi Irene, thanks for stopping by
The point I keep trying to make is that is not about barefoot or not, which is how many try to frame the debate. Its about the propaganda and rhetoric (and lies?) that gets used.
Do you agree with the statements by Vivobarefoot and the many barefoot bloggers who emphatically state that the study by Daoud et al proves that barefoot running is better? This was a retrospective study on 56 almost elite level runners that found the injury rate in heel strikers where double the forefoot strikers. Given that they were all wearing shoes and not typical of the average runner, how does that show anything about barefoot?, ....especially in the context of Kleindienst (2003) - 471 runners; no difference between rearfoot and forefoot strikers concerning the frequency of injury. Walther (2005) - 1203 runners; no difference in incidence of injury between rearfoot and forefoot strikers.
Do you agree with the claims discussed on the first page of this thread that children who wear shoes will be intellectually impaired compared to children that don't? (and people wonder why they ridiculed!)
The above are just three examples of many. As I have said a zillion times:
Quote:
Originally Posted by Craig Payne
continually misuse, misrepresent, misquote and misinterpret the research?
As for the injury rates, the only claims I make are that barefoot runners get injuries. We see them in our clinics. Visit any barefoot website and they are full of people asking for advice on their injury! Why does the rhetoric and propaganda claim that you don't get an injury running barefoot?
...that is my point.
__________________ Craig Payne
__________________________________________________ ___________________________________ Follow me on Twitter | Run Junkie God put me on this earth to accomplish a certain number of things - right now I am so far behind, I will never die.
I believe the rhetoric is that you will get injured less. Lets wait for the prospective data.
Irene
While meanwhile what the science apparently tells us is that you will get injured differently.
I find the idea of prospective trials on injury intriguing. Personally, I don't believe they can be performed with enough control of all of the variables at play here.
Lets say we take two groups of individuals and have one set run barefoot while the others runs shod, we see more injuries in one group of runners and conclude that this style of running results in more injuries- right? Hold your horses, unless every possible predictor of running related injury is precisely matched within the two groups you're skating on thin ice. You might get close using monozygotic twins, but even then you'll only be getting close.
For example, we have suggestions of a genetic marker for achilles tendonosis- will such a study test all of the individuals within the study for this marker? Doubtful. Indeed, it has been suggested that those with blood group O are more susceptible to tendonitis, and specifically Achilles tendonitis; will participants in the study be matched for blood group? Doubtful. And that is just a couple of examples. Too many variables to control for to make for any meaningful study. But then according to some blog-sites "I've got an axe to grind". It's true, I'm anti-poor science.
But then according to some blog-sites "I've got an axe to grind". It's true, I'm anti-poor science.
Another "Angry Podiatrist?".....I hope so.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Have fun in Manchester Kevin. Sorry I can't be there, but you know why I won't attend.
Simon:
Won't quite be the same without you in Manchester but am looking forward to hanging out with Bartold for the first time in quite a few years. Most of all, I'm looking forward to our week's vacation after the seminar in the Scottish Highlands close to Fort William.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Re: There is no barefoot running debate
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