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Purpose: This retrospective study tests if runners who habitually forefoot strike have different rates of injury than runners who habitually rearfoot strike.
Methods: We measured the strike characteristics of middle and long distance runners from a collegiate cross country team and quantified their history of injury, including the incidence and rate of specific injuries, the severity of each injury, and the rate of mild, moderate and severe injuries per mile run.
Results: Of the 52 runners studied, 36 (59%) primarily used a rearfoot strike and 16 (31%) primarily used a forefoot strike. Approximately 74% of runners experienced a moderate or severe injury each year, but those who habitually rearfoot strike had approximately twice the rate of repetitive stress injuries than individuals who habitually forefoot strike. Traumatic injury rates were not significantly different between the two groups. A generalized linear model showed that strike type, sex, race distance, and average miles per week each correlate significantly (p<0.01) with repetitive injury rates.
Conclusions: Competitive cross country runners on a college team incur high injury rates, but runners who habitually rearfoot strike have significantly higher rates of repetitive stress injury than those who mostly forefoot strike. This study does not test the causal bases for this general difference. One hypothesis, which requires further research, is that the absence of a marked impact peak in the ground reaction force during a forefoot strike compared to a rearfoot strike may contribute to lower rates of injuries in habitual forefoot strikers.
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
We have to go where the evidence takes us, but:
- retrospective
- specific sample (high level college runners)
The breakdown in type of injury differences interesting:
MTSS - no differences
knee pain - no differences
ITB - no differences
Achilles tendon (more in forefoot strikers in females, but not males)
Plantar fasciitis (more in rearfoot strikers in females, but not males)
Met stress fractures - no differences
Hip pain (more in rearfoot strker)
Tibial stress fractures - no differences
"repetivie joint sprain" - more in rearfoot strikers
Tib post tendonopathy - no differences
It is puzzling that there are so many "no differences" in individual injuries, but such a big difference when they all pooled.
__________________ Craig Payne
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Last edited by NewsBot : 12th January 2012 at 08:02 PM.
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
This one has also just gone online in the same journal by Lieberman's colleagues
Effects of Footwear and Strike Type on Running Economy
ABSTRACT Purpose. This study tests if running economy differs in minimal shoes versus standard running shoes with cushioned, elevated heels and arch supports, and in forefoot versus rearfoot strike gaits. Methods. We measured the cost of transport (mlO2/kg/m) in subjects who habitually run in minimal shoes or barefoot while they were running at 3.0 m/s on a treadmill during forefoot and rearfoot striking while wearing minimal and standard shoes, controlling for shoe mass and stride frequency. Force and kinematic data were collected when shod and barefoot to quantify differences in knee flexion, arch strain, plantarflexor force production, and Achilles tendon- triceps surae strain. Results. After controlling for stride frequency and shoe mass, runners were 2.41% more economical in the minimal shoe condition when forefoot striking and 3.32% more economical in the minimal shoe condition when rearfoot striking (p<0.05). In contrast, forefoot and rearfoot striking did not differ significantly in cost for either minimal or standard shoe running. Arch strain was not measured in shoes condition but was significantly greater during forefoot than rearfoot striking when barefoot. Plantarflexor force output was significantly higher in forefoot than rearfoot striking, and in barefoot than shod running. Achilles tendon-triceps surae strain and knee flexion were also lower in barefoot than standard shoe running. Conclusions. Minimally shod runners are modestly but significantly more economical than traditionally shod runners regardless of strike type, after controlling for shoe mass and stride frequency. The likely cause of this difference is more elastic energy storage and release in the lower extremity during minimal shoe running. Key Words: running economy, barefoot running, minimal shoe running, forefoot strike, rearfoot strike.
PURPOSE/HYPOTHESIS: Reports of a lower prevalence of injuries in habitual
barefoot (BF) runners have encouraged research to assess the influence
of this running style on injury potential. BF running is promoted based
on its forefoot contact pattern and the associated reduction of the vertical
ground reaction force (vGRF) impact transient. However, the effect
of exertion on BF running foot contact (FC) patterns has not been examined.
For example, novice BF runners may fatigue more readily than experienced
BF runners, and thus alter foot/surface contact patterns and
joint demands in a way that could put themselves at increased risk of injury.
The purpose of this study was to (1) quantify the changes in ankle
kinematics at FC, and (2) to characterize the biomechanical demand at
the ankle, knee, and hip in novice BF runners, before and after exertion.
NUMBER OF SUBJECTS: Three.
MATERIALS/METHODS: Three habitually shod distance runners performed
overground BF running at their self-selected speed, before and after exertion.
All subjects included in the study ran a minimum of 12 kilometers
(km) per week, and reported no significant injuries over the preceding 12
months. The exertion protocol was a BF run of 1.6 km at their self-selected
speed. Kinematics were recorded using a Qualisys motion capture system
(Gothenburg, Sweden) at 250 Hz. Three-dimensional kinetics were
recorded from AMTI force platforms (Watertown, MA) at 1500 Hz. FC
was defined as a minimum of 20 Newtons vGRF. The support moment
was calculated as the sum of the sagittal plane extensor moments during
the absorption (first half of the stance) phase of running. Mean absolute
differences, or relative contributions, and the associated effect sizes (ES;
Cohen’s d) between the 2 conditions are reported.
RESULTS: Following the exertion protocol, the ankle position changed
from a position of plantar flexion (–10.27°) to dorsiflexion (3.38°; ES
2.32), suggesting a heel strike FC. The relative contribution of the ankle
and hip was observed to decrease appreciably (43.4% to 36.9%; ES: 1.14
and 11.0% to 8.7%; ES: 0.35, respectively), while the demand at the knee
increased (45.8% to 54.4%; ES: 1.13).
CONCLUSIONS: The findings from this preliminary investigation suggest
that exertion changes BF running mechanics in a way that negates any
potential benefits associated with this running style. In particular, subjects
reverted to a heel strike FC pattern and exhibited an increase in the
biomechanical demand at the knee following exertion.
CLINICAL RELEVANCE: The findings suggest that training programs designed
to transition runners from shod to BF should consider the effects of exertion
on running mechanics.
__________________ Craig Payne
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Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
I don't think it's at all helpful to publish retrospective research in this area. With such specific subjects as Craig says.
I wanted to support those points regarding injury pooling; I have not read the paper(s) as yet, am keen if anyone is willing to share (rik.mellor@smuc.ac.uk), but I'm very interested to understand what 'hip pain' and 'repetitive joint sprain' are for starters and how accurate the clinical diagnoses can be for repetitive or traumatic injury classification.
Plus were subjects matched on volume, intensity, surface etc, as well as mileage, do collegiate cross country runners become injured from varied terrain and gradient? With these in mind for me 16 forefoot strike subjects sounds a small percentage.
You can bet there will be further related research to follow from Harvard.
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by rikmellor
I don't think it's at all helpful to publish retrospective research in this area. With such specific subjects as Craig says.
I wanted to support those points regarding injury pooling; I have not read the paper(s) as yet, am keen if anyone is willing to share (rik.mellor@smuc.ac.uk), but I'm very interested to understand what 'hip pain' and 'repetitive joint sprain' are for starters and how accurate the clinical diagnoses can be for repetitive or traumatic injury classification.
Plus were subjects matched on volume, intensity, surface etc, as well as mileage, do collegiate cross country runners become injured from varied terrain and gradient? With these in mind for me 16 forefoot strike subjects sounds a small percentage.
You can bet there will be further related research to follow from Harvard.
As long as Vibram is funding these studies, I'm sure that Lieberman's group will cook up some more research studies to support barefoot, minimalist, non-heel strike running. There's money in them thar five-toed shoes!!
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
In an email from Vivobarefoot, they said the following:
Quote:
Originally Posted by Vivobarefoot
Hot off the press, groundbreaking research led by Harvard University Professor Daniel Lieberman, is going to send shockwaves throughout the entire footwear industry.
Over the last four decades, since the invention of modern running footwear, shoe companies have focused on shock absorbing technologies to promote heel striking movement. But as this new research has discovered running whilst landing on the heel is TWICE as likely to cause injury than the alternative fore-foot strike, or as we know it - skillful barefoot running.
Since 2003 VIVOBAREFOOT has worked on making footwear that mimics natural movement. We have always believed barefoot is best, it's now fact.
In an email from Vivobarefoot, they said the following:
Quote:
has discovered running whilst landing on the heel is TWICE as likely to cause injury than the alternative fore-foot strike, or as we know it - skillful barefoot running.
Someone needs to explain to them how to interpret the results from a retrospective study. ..... but, Ian predicted that this is how they will interpret it!
__________________ Craig Payne
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Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by Craig Payne
Someone needs to explain to them how to interpret the results from a retrospective study. ..... but, Ian predicted that this is how they will interpret it!
Yep, wasn't a tough call in fairness. They are all at it on twitter. It's confirmation bias crazy over there.
Another observation regarding the latest "Lieberman study"... When was the last time a 6th author of a piece of work ever had so much attention/exposure for said piece of work?
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Some of them just don't get it do they?
See this for how one barefoot blogger interpreted the research (see the attachment; I attached it in case they remove it from the site when they realise how big of a fool they making of themselves)).
Someone needs to point out that there is nothing "official" about it; that is was only a retrospective study; that it was only on a small group of almost elite runners; that it was not even on barefoot runners; and certainly was NOT comparing a "jogger" to "skilled barefoot" ... and they wonder why they get ridiculed and make fools of themselves with their continued misrepresentation, misunderstanding, misquoting and misusing research?
Liebermann, after his Nature publication had to take the extraordinary and unprecedented step of publishing a disclaimer on his website to distance himself from the interpretation that so many barefoot bloggers were making from that research. I wonder how long before he has to publish a disclaimer to distance himself from this one!
Its actually a good piece of research and contributes some good information to our understanding of the topic ... its just the nonsensical interpretations that fools are making of it.
__________________ Craig Payne
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Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by rikmellor
I wanted to support those points regarding injury pooling; I have not read the paper(s) as yet, am keen if anyone is willing to share (rik.mellor@smuc.ac.uk), but I'm very interested to understand what 'hip pain' and 'repetitive joint sprain' are for starters and how accurate the clinical diagnoses can be for repetitive or traumatic injury classification.
The diagnoses were probably accurate, but there are potential issues with the retrospective nature of the diagnoses for classification. But that is always an issue with retrospective studies and there is not necessarily an easy way around it. As with any retrospective study design its lower down in the hierarchy of evidence (someone need to explain that to the barefooters making all the wild claims from this study!)
Quote:
Plus were subjects matched on volume, intensity, surface etc, as well as mileage, do collegiate cross country runners become injured from varied terrain and gradient? With these in mind for me 16 forefoot strike subjects sounds a small percentage. .
They were all coached by the same coach; ran the same distances; etc etc, so I comfortable with that.
Quote:
Originally Posted by Kevin Kirby
As long as Vibram is funding these studies, I'm sure that Lieberman's group will cook up some more research studies to support barefoot, minimalist, non-heel strike running. There's money in them thar five-toed shoes!!
I do not necessarily have a problem with that. You have to trust the integrity of the researchers regardless of the funding source. If you going to dismiss any of Liebermanns research as he is funded by a barefoot company, then we have to also dismiss any positive research on running shoes funded by running shoe companies. We can't have it both ways (and neither can the barefoot running bloggers!). Where the biases tend to come in for this sort of case, is not the conduct and analysis of the research, but in the spin that might get put on it in the discussion. The problem is, so many put blind faith in the spin and not the data (classic egs are spin in papers like Craig Richard's systematic review on the evidence for running shoe; the spins the Robbins & Gouw etc put on there really good research - in their case the spin pretty much ruined it).
__________________ 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.
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Craig:
I would tend to agree that Lieberman and company did a pretty good job with this paper and thought they were pretty fair, but obviously biased toward forefoot strikers. I found it very interesting (as you did in a previous posting) at how few of the injuries showed signficance of forefoot vs rearfoot strikers.
From their injury table below the only significant (p<0.05) differences in injuries when both male and female injuries were combined were as follows:
Rearfoot strikers had just barely significant (p = 0.0401) increases in "hip pain" vs forefoot strikers.
Rearfoot strikers had just barely signficant (p = 0.0417) increases in "repetitive joint sprain" (whatever that is?) vs forefoot strikers.
So, if the researchers weren't so intent on showing that forefoot striking was a better way to run, maybe they would have concluded, from an analysis of the table below from their paper the following:
Quote:
In the 23 running injury types that were categorized in the 16 forefoot striking and 36 rearfoot striking runners within this small study, there were only 2 of these 23 running injury types that showed a slight significant difference between the forefoot striking and rearfoot striking runners. Both hip pain and repetitive joint sprain were more signficant in the rearfoot striking runners. However, over twice as many collegiate distance runners chose to foot strike with their rearfoot rather than their forefoot which certainly indicates that rearfoot striking running is the preferred method of running in these Division I male and female collegiate distance runners.
I don't think we would ever see Dan Lieberman write an abstract like that, certainly not as long as Vibram is funding his website and all of his running research.
__________________
Sincerely,
Kevin
**************************************************
Kevin A. Kirby, DPM
Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine at Samuel Merritt College
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by Craig Payne
The diagnoses were probably accurate, but there are potential issues with the retrospective nature of the diagnoses for classification.
Craig, hopefully you can help me with this one....
Why would they have no calculation of effect size or clinical relevance? How do we know the size of the effect even practically relevant? I'm certainly no expert on stats and was hoping you may be able to provide insight. Do you calculate effect size/clinical relevance in a retrospective study? I just find it strange that they have ommitted this, given that this journal makes specific reference to the need to include these calculations when submitting to their journal. Would their be a reason for this? It may or may not make any difference anyway.
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by Kevin Kirby
As long as Vibram is funding these studies, I'm sure that Lieberman's group will cook up some more research studies to support barefoot, minimalist, non-heel strike running. There's money in them thar five-toed shoes!!
Of course there is money in the big stability shoes as well. Again, this is not a professional attitude. It is right to criticise the funding that goes into these papers. However, one should primarily focus on the results and methods used, because the funding works both ways and cannot possibly be used as an argument.
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by AlexDP
Of course there is money in the big stability shoes as well. Again, this is not a professional attitude. It is right to criticise the funding that goes into these papers. However, one should primarily focus on the results and methods used, because the funding works both ways and cannot possibly be used as an argument.
Yes it can it shows Bias
That is why a conflict of interest must always be stated in a research paper
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by mike weber
Yes it can it shows Bias
That is why a conflict of interest must always be stated in a research paper
as I said above:
Quote:
Originally Posted by Craig Payne
I do not necessarily have a problem with that. You have to trust the integrity of the researchers regardless of the funding source. If you going to dismiss any of Liebermanns research as he is funded by a barefoot company, then we have to also dismiss any positive research on running shoes funded by running shoe companies. We can't have it both ways (and neither can the barefoot running bloggers!). Where the biases tend to come in for this sort of case, is not the conduct and analysis of the research, but in the spin that might get put on it in the discussion. The problem is, so many put blind faith in the spin and not the data (classic egs are spin in papers like Craig Richard's systematic review on the evidence for running shoe; the spins the Robbins & Gouw etc put on there really good research - in their case the spin pretty much ruined it).
I have been involved in and conducted industry sponsored research; my previous employment was right in the middle of a lot of drug industry sponsored clinical trials ... you have to trust the integrity of people when it comes to the conduct of research.
Where the bias come in are in the spin that often get placed on the interpretation of the results. Here is a classic: Plantar fasciitis symptoms and two different running shoes in which they clearly screwed up the analysis to paint the sponsors shoes in a better light. Try and convince me that they did not do what they did because Nike sponsored it.
Probably the worst one is the now thoroughly discredited and withdrawn paper in Lancet by Andrew Wakefield that started the whole MMR and autism scare that has now been clearly shown to be false and has led to a huge public health risk. If some of his funding sources were declared at the time, more questions would have been asked prior to publication and his fraud would not have been perpetuated. Despite what I said above about trusting the integrity of researchers, this is one case where the integrity of the researcher has been shown to be extremely misplaced.
__________________ 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.
Last edited by Craig Payne : 12th April 2012 at 03:52 PM.
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Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by pod29
Craig, hopefully you can help me with this one....
Why would they have no calculation of effect size or clinical relevance? How do we know the size of the effect even practically relevant? I'm certainly no expert on stats and was hoping you may be able to provide insight. Do you calculate effect size/clinical relevance in a retrospective study? I just find it strange that they have omitted this, given that this journal makes specific reference to the need to include these calculations when submitting to their journal. Would their be a reason for this? It may or may not make any difference anyway.
I not totally sure how appropriate it is, but I did an effect size (Cohen's D) on Table two of their data; just the first line of mild repetitive injuries (ALL) and the effect size of the difference was 3.4 (assuming my maths was right!) ... that is as good as it gets! ... unfortunately there is not enough data they provided on the overall rate between the two groups to do an overall effect size (can only do it on each row of table two).
I not sure why the authors did not do the effect size or why the journal's reviewers did not require it. It certainly would be helpful to put the whole interpretation into a better context. Given that there are a number of categories in which there was no difference in the injury rate, the effect size could potentially not be very good at all....would like that data to see!
The closest I can get is this in paragraph 20:
Quote:
injury rates for both mild and moderate (but not severe)
repetitive stress injuries are 2.5 times higher in RFS than FFS runners (p<0.05), and the rate of
combined moderate and severe repetitive injuries is 1.7 times more frequent in RFS runners
(8.66 injuries per 10,000 miles) than FFS runners (5.00 injuries per 10,000 miles; p = 0.04)
so that's 8.66 injuries vs 5.00 injuries for moderate and severe, but we need the SD to do an effect size calculation. As far as I can see, they did not give us the overall numbers for the mild and moderate!If I was a reviewer I would have requested it.
The more I delve into this paper, the more shortcomings I see in what they are reporting and analyzing.
Perhaps someone with a better understanding of effect sizes than me can comment.
__________________ Craig Payne
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Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by Craig Payne
I not totally sure how appropriate it is, but I did an effect size (Cohen's D) on Table two of their data; just the first line of mild repetitive injuries (ALL) and the effect size of the difference was 3.4 (assuming my maths was right!) ... that is as good as it gets! ... unfortunately there is not enough data they provided on the overall rate between the two groups to do an overall effect size (can only do it on each row of table two).
I not sure why the authors did not do the effect size or why the journal's reviewers did not require it. It certainly would be helpful to put the whole interpretation into a better context. Given that there are a number of categories in which there was no difference in the injury rate, the effect size could potentially not be very good at all....would like that data to see!
The closest I can get is this in paragraph 20: so that's 8.66 injuries vs 5.00 injuries for moderate and severe, but we need the SD to do an effect size calculation. As far as I can see, they did not give us the overall numbers for the mild and moderate!If I was a reviewer I would have requested it.
The more I delve into this paper, the more shortcomings I see in what they are reporting and analyzing.
Perhaps someone with a better understanding of effect sizes than me can comment.
I'd start by just doing an unstandardised ratio- how many injuries in group one versus how many injuries in group 2.
...and they wonder why we ridicule and mock them! They only have themselves to blame.
__________________ Craig Payne
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I expect that this one would have been over their heads :-(
__________________ Craig Payne
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Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Here's one of my concerns with the study:
Other researchers who have studied foot strike actually during an event found only 1.4% (Haegawa, et. al., 2007) and 1.8% (Larsen et. al,. 2011) of their running populations to be forefoot strikers. Lieberman concluded that over 31% of his cohort hit the ground forefoot first. 31%! Why so many forefoot strikers in Lieberman's paltry 52 total cohort?
It is clear from the Haegawa and Larsen studies (with large populations) that both high-quality recreational and elite athletes change their strike patterns from forefoot to rearfoot during the race -- perhaps due to muscle fatigue and reduced speed towards the end of the event -- i.e., forefoot to mid-foot at around 10K, and mid-foot to rearfoot at around 32K (Larsen et. al,. 2011). I have not read Lieberman's study protocol, but my guess is that he assessed the strike patterns of his population from a few high-speed video frames taken from a short period of running, which is probably why his cohort of forefoot strikers is so much higher than reported in previous studies. Therefore, one might be forgiven in assuming that many of Lieberman's forefoot strikers (perhaps 29% of them!) may actually become rearfoot strikers during a race, which means his results should perhaps be treated with some caution.
References:
1. Hasegawa H, Yamauchi T, Kraemer WJ.: Foot strike patterns of runners at the 15-km point during an elite-level half marathon. J Strength Cond Res. 2007 Aug;21(3):888-93.
Abstract
There are various recommendations by many coaches regarding foot landing techniques in distance running that are meant to improve running performance and prevent injuries. Several studies have investigated the kinematic and kinetic differences between rearfoot strike (RFS), midfoot strike (MFS), and forefoot strike (FFS) patterns at foot landing and their effects on running efficiency on a treadmill and over ground conditions. However, little is known about the actual condition of the foot strike pattern during an actual road race at the elite level of competition. The purpose of the present study was to document actual foot strike patterns during a half marathon in which elite international level runners, including Olympians, compete. Four hundred fifteen runners were filmed by 2 120-Hz video cameras in the height of 0.15 m placed at the 15.0-km point and obtained sagittal foot landing and taking off images for 283 runners. Rearfoot strike was observed in 74.9% of all analyzed runners, MFS in 23.7%, and FFS in 1.4%. The percentage of MFS was higher in the faster runners group, when all runners were ranked and divided into 50 runner groups at the 15.0-km point of the competition. In the top 50, which included up to the 69th place runner in actual order who passed the 15-km point at 45 minutes, 53 second (this speed represents 5.45 m x s(-1), or 15 minutes, 17 seconds per 5 km), RFS, MFS, and FFS were 62.0, 36.0, and 2.0%, respectively. Contact time (CT) clearly increased for the slower runners, or the placement order increased (r = 0.71, p < or = 0.05). The CT for RFS + FFS for every 50 runners group significantly increased with increase of the placement order. The CT for RFS was significantly longer than MFS + FFS (200.0 +/- 21.3 vs. 183.0 +/- 16 millisecond). Apparent inversion (INV) of the foot at the foot strike was observed in 42% of all runners. The percentage of INV for MFS was higher than for RFS and FFS (62.5, 32.0, and 50%, respectively). The CT with INV for MFS + FFS was significantly shorter than the CT with and without INV for RFS. Furthermore, the CT with INV was significantly shorter than push-off time without INV for RFS. The findings of this study indicate that foot strike patterns are related to running speed. The percentage of RFS increases with the decreasing of the running speed; conversely, the percentage of MFS increases as the running speed increases. A shorter contact time and a higher frequency of inversion at the foot contact might contribute to higher running economy.
2. Kaminski J, Decker T, Preble J, Lyons D, McIntyre K, Normile A. Larson P, : Foot strike patterns of recreational and sub-elite runners in a long-distance road race. J Sports Sci. 2011 Dec;29(15):1665-73. Epub 2011 Nov 18.
Department of Biology , St. Anselm College , Manchester , New Hampshire , USA.
Abstract
Although the biomechanical properties of the various types of running foot strike (rearfoot, midfoot, and forefoot) have been studied extensively in the laboratory, only a few studies have attempted to quantify the frequency of running foot strike variants among runners in competitive road races. We classified the left and right foot strike patterns of 936 distance runners, most of whom would be considered of recreational or sub-elite ability, at the 10 km point of a half-marathon/marathon road race. We classified 88.9% of runners at the 10 km point as rearfoot strikers, 3.4% as midfoot strikers, 1.8% as forefoot strikers, and 5.9% of runners exhibited discrete foot strike asymmetry. Rearfoot striking was more common among our sample of mostly recreational distance runners than has been previously reported for samples of faster runners. We also compared foot strike patterns of 286 individual marathon runners between the 10 km and 32 km race locations and observed increased frequency of rearfoot striking at 32 km. A large percentage of runners switched from midfoot and forefoot foot strikes at 10 km to rearfoot strikes at 32 km. The frequency of discrete foot strike asymmetry declined from the 10 km to the 32 km location. Among marathon runners, we found no significant relationship between foot strike patterns and race times.
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Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Quote:
Originally Posted by Ray Anthony
Here's one of my concerns with the study:
Other researchers who have studied foot strike actually during an event found only 1.4% (Haegawa, et. al., 2007) and 1.8% (Larsen et. al,. 2011) of their running populations to be forefoot strikers. Lieberman concluded that over 31% of his cohort hit the ground forefoot first. 31%! Why so many forefoot strikers in Lieberman's paltry 52 total cohort?
Agreed. I am slowly working my way through the paper and had already annotated my copy with a similar question. Strike characterisation was done for some subjects on a treadmill and some on a track. Might this account for the high percentage of forefoot strikers in the subject population?
Re: Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Not sure if the following has been discussed/found as yet...
[Frankly, I'm a bit fed up with the whole barefoot running issue (& I would be considered one of the more considerate towards this position/movement based on my personal involvement with barefoot/minimalist running)].
Hence I haven't bothered keeping track of recent discussions on this topic. Yet, I felt the following was best posted on this thread due to the recent advert submitted by shoe company Vivobarefoot regarding foot strike. Submitted on their website here (link) on the 12th Jan. 2012... "Proven. It's official - barefoot is best"...
Is it any wonder why Podiatrists get annoyed ... yet the wilful (narrow minded) perception of this annoyance is seen to be directly related/targeted to the concept (barefoot/minimalist running) & not the interpretation & subsequent conveying of the information to the lay public. Isolating one issue (i.e. foot strike) targeted to the masses without the consideration of multiple biomechanical factors is nonsensical (&/or irresponsible/negligent) in the above advertised context. Like I've said before, based on one's position - it would seem fame, fortune & what can be perceived as idiosyncrasy, reigns precedence over science, logic, reason, honesty & common sense for many in this deemed 'barefoot' movement/industry.
For those cardinal exponents in the barefoot brigade... using tactics such as smoke & mirrors to fulfil an agenda has not & will not cut it in the future... hence the viewpoint of many on this forum.
When all is said & done... one's own physical condition will let one know what is appropriate at a given time or future endeavour. Pain is an effective mediator on this topic... no matter what your inclination on foot attire. Our (i.e. Podiatrist's) role is to treat pain... better still - prevent it from occurring! The above Vivobarefoot submission can lead to consequences to the contrary.
Foot Strike and Injury Rates in Endurance Runners: a retrospective study
Agreed. I am slowly working my way through the paper and had already annotated my copy with a similar question. Strike characterisation was done for some subjects on a treadmill and some on a track. Might this account for the high percentage of forefoot strikers in the subject population?
... yet the wilful (narrow minded) perception of this annoyance is seen to be directly related/targeted to the concept (barefoot/minimalist running) & not the interpretation & subsequent conveying of the information to the lay public. Isolating one issue (i.e. foot strike) targeted to the masses without the consideration of multiple biomechanical factors is nonsensical (&/or irresponsible/negligent) in the above advertised context. Like I've said before, based on one's position - it would seem fame, fortune & what can be perceived as idiosyncrasy, reigns precedence over science, logic, reason, honesty & common sense for many in this deemed 'barefoot' movement/industry.
Linear Mode
