Image via WikipediaOne of the major arguments posited by many for running barefoot or in minimalist shoes is that doing so reduces the likelihood of injury. However, although I trend toward minimalism in my own shoe preferences, I’ll be completely honest and admit that no study has confirmed that barefoot/minimalist running in fact reduces injury rates in runners (similarly, to my knowledge no study has shown that modern, high-tech shoes do either). Given this, where does this belief in the injury reducing capacity of barefoot/minimalist running come from?
In the absence of studies examining the link between shoes/minimalist shoes/lack of shoes and injury risk, what we are left with is anecdotal evidence – many runners have reported overcoming old or nagging injuries by shedding their shoes or running in a minimalist shoe like the Vibram Fivefingers. However, for every runner who reports being cured of old running injuries, a seemingly equal number of barefoot/minimalist runners succumb to injuries like the dreaded “top of foot pain” or metatarsal stress fractures. It is quite possible that many of these injuries are due to people doing too much too soon in a shoe that their body is simply not adapted to, and it is therefore hard to know if these injuries would still occur if a longer, easier adaptation regimen was followed. It is also possible that some people simply cannot tolerate running barefoot or in a very minimal shoe due to the unique structure of their body (human variation is very real, this I do firmly believe).
Rather than dwell on the larger injury debate too much here, I want to focus on just one aspect – why do some runners seem to overcome injuries after making the switch to running barefoot/minimalist?
One of the things that many people notice when switching to a barefoot/minimalist running style is that their stride begins to change. Types of changes observed include a change in footstrike from heel to mid/forefoot, a shorter stride, and a faster turnover. I unfortunately never took the time to count my stride rate prior to going minimalist, but my sense is that mine has increased, and 3 recent measurements (on different runs) all put me at a cadence of 180 steps/minute. Stride length is harder to gauge, but wear patterns on my shoes do suggest that my heel strike has diminished considerably, and I can clearly tell that I land either midfoot or forefoot when I run in my Vibram Fivefingers (I tend to alternate between the two footstrikes while I run in them). These same types of observations are noted repeatedly by runners who make the switch.
Given the above, one might hypothesize that one of the ways that going barefoot/minimalist might help some people is that it facilitates a change in running gait, and that change in some way ameliorates problems that were causing trouble for some people. After this long introduction, this is where the study by Dr. Bryan Heiderscheit and colleagues of the University of Wisconsin referred to in the title comes in. I will state at the outset that I have not read the study yet (I am trying to get ahold of it – I really wish all journals were open access!), but it has been reported on by two people who’s opinions I respect: Alex Hutchinson on Sweat Science and The Globe and Mail, and Amby Burfoot on the Peak Performance Blog.
In a nutshell, Heiderscheit studied the effects of stride rate (both increased and decreased) on gait in 45 recreational runners. They had each runner run (in their own shoes) on a treadmill at stride rates both 5% and 10% below (slower cadence) and above (faster cadence) their preferred stride rate. According to the abstract of the study, the results yielded the following:
“Less mechanical energy was absorbed at the knee (p less than 0.01) during the +5% and +10% step rate conditions, while the hip (p less than 0.01) absorbed less energy during the +10% condition only. All joints displayed substantially (p less than 0.01) more energy absorption when preferred step rate was reduced by 10. Step length (p less than 0.01), center of mass vertical excursion (p less than 0.01), breaking impulse (p less than 0.01) and peak knee flexion angle (p less than 0.01) were observed to decrease with increasing step rate. When step rate was increased 10% above preferred, peak hip adduction angle (p less than 0.01), as well as peak hip adduction (p less than 0.01) and internal rotation (p less than 0.01) moments, were found to decrease.“
What this shows is that running with a faster cadence/higher stride rate reduced loading on the knee and hip, allowed for a more level carriage of the center of mass (less vertical oscillation), shortened stride length, and created less braking impulse. All of this is very interesting, and seems to provide a possible explanation for why at least some runners are able to overcome injuries by going barefoot/minimalist. The reasoning goes like this: suppose a runner has a history of knee or hip injury, and decides to make a radical change and ditch their shoes or start running in something very minimal. Associated with this change, their stride begins to shorten, and their turnover increases. What Heiderscheit has shown is that in doing this, they also might be reducing impact forces on the knee and hip. The leap is then to say that reducing mechanical energy being absorbed at those joints in some way “cures” the injury. This last part, unfortunately, is the link that still needs to be made, but according to Alex Hutchinson’s article in The Globe and Mail, Heiderscheit has indicated that “a randomized, controlled trial comparing increased stride rate to standard care for knee pain and iliotibial band syndrome, with a one-to-two-year follow-up, is in the works.” The results of such a study will be very interesting to see.
I want to next address some information presented in a fascinating interview that Amby Burfoot conducted with Dr. Heiderscheit on the Peak Performance blog – I highly recommend that you read it. Among the interesting tidbits from the interview are the following:
1. In the interview, Heiderscheit points out that the idea for conducting the study came from observation of runners in their clinic – they noticed that many patients reported that their knees felt better when they ran fast (which also implies faster cadence). This is a great example of how anecdotes can drive interesting research, and it’s refreshing to hear this. All too often scientists like to push aside anecdotal evidence, when in actuality it can be the greatest source of inspiration for research. What we are seeing right now in the barefoot/minimalist debate is tons of anecdote and little hard research, but my hope is that the anecdotes that are out there will drive researchers to ask and address new and interesting questions.
2. In response to a question posed by Burfoot regarding what he thought might happen if his subjects had worn racing flats, Heiderscheit responded that: “I’d guess, and this is just speculation, that they wouldn’t run the same as in the training shoes. I think they would have selected a preferred stride rate close to our +5 percent condition.” Burfoot goes on to ask about whether “thick, cushioned shoes” encourage runners to take a longer stride, to which Heiderscheit responds that there is lots of variability (as I would expect), but that it “seems like a reasonable conclusion.“
3. Heiderscheit addresses the fact that runners in his study perceived a higher degree of exertion at a faster stride rate by pointing out that it takes time to adapt to a new stride and not feel “goofy” doing it. This is my experience exactly – any time I try something new with my running gait it feels weird at first, but with practice it tends to become much more comfortable.
As I mentioned above, there’s a lot more interesting stuff in Burfoot’s interview with Dr. Heiderscheit, check it out here: http://peakperformance.runnersworld.com/2010/08/aug-24-new-study-reports-that-shorter-strides-can-have-many-benefits.html
I’ll end with a few observations of my own.
1. Despite the interesting findings presented in this study regarding the potential benefits of a shorter, quicker stride, Dr. Heiderscheit clearly points out that they have not linked reduced impact force on joints to injury reduction. He does, however, indicate in Burfoot’s interview that anecdotal evidence from the clinic seems to support this contention – until the results of an injury study come out, that is what we have to go on.
2. Does this study “prove” that barefoot/minimalist running is better? I want to address this because I often see how results of studies like this can be taken too far to support a point (I’ve probably done it myself from time to time). It’s important to note that Heiderscheit’s study was neither intended nor designed to address the benefits of barefoot/minimalist running. I’d suspect, though I can’t be sure, that most of the runners in the study were wearing modern, thick soled shoes. So it’s entirely possible that the benefits of a shorter, faster stride are independent of footwear.
What I do find intriguing is that many people observe a fairly rapid shift in gait when they begin a move into barefoot/minimalist running. I have experienced this myself. Thus, it is possible that going barefoot/minimalist could help you in a gait transition, which could in turn help you to reap some of the benefits conferred to the subjects in Heiderscheit’s study when running at increased cadence. People should still be aware that making this transition does carry some risk as the body needs time to adapt to the different forces applied to the feet and legs in barefoot/minimalist running, and that a transition needs to be made slowly and carefully. However, if the transition can be accomplished safely and successfully, and the end benefit is less impact on the knees and hips (and this is shown at some point to reduce injury rates), a slow, steady transition just might be worth it.
3. A question that I have been mulling related to the previous point is what is the long term effect of shortening stride in a thickly cushioned shoe with a lifted heel? If the trend in this study was that runners experienced reduced force on the knees and hips at a stride rate faster than their preferred rate, is it possible that running in a thickly cushioned shoe with a lifted heel encourages a slower cadence/longer stride with higher knee/hip impact, at least in some people (I’m again making the assumption that most of the runners in this study wore this type of shoe)? People running barefoot are advised to shorten stride and increase cadence (often seems to happen automatically), because to do the opposite would hurt (though even Daniel Lieberman’s Nature paper reported some barefoot heel strikers). Could advising people to shorten stride in a lifted shoe potentially be problematic? This was touched on a bit in the Burfoot interview, but one wonders if you train at a stride rate faster than preferred in heel lifted shoes, is there anything problemaic with this? I don’t know the answer to these questions, or if they even matter, but it would be interesting to see them addressed (I’m basically just thinking out loud here…).
4. I’ve said this a number of times recently, but the best way to see how something like an increased stride rate might benefit you is to try it yourself. If you have a history of knee, ITB, or hip issues, maybe a shorter, faster stride is the way to go. Head out and try focusing on getting your foot to land a bit closer to your hips, or you can use a cue like that suggested by Steve Magness to “put your foot down behind you” – it’s not what really happens, but it’s helpful to make you conscious of your landing location. It will likely feel strange at first, but as I have found it does get more comfortable with time. If you need encouragement, I particularly like the final quote from Dr. Heiderscheit’s interview with Amby Burfoot: “…the big picture is, if you change the big forces by lowering the center of gravity displacement and lowering the landing impacts, I can’t see how that can be a bad thing for any injury.“
You might also like:
Podcast: Physiotherapist Blaise Dubois on Running Injuries, Form, Footwear, and Barefoot Running
Irene Davis Lecture on Running Shoes, Form, and Injuries: A Must Watch for Anyone Interested in the Minimalist/Barefoot Running Debate
Dathan Ritzenhein Switches from Heel to Midfoot Strike: "I think I’m more efficient"
Thoughts on Daniel Lieberman’s Barefoot Running Paper
Footwear and Pronation – A Slow-Motion View from Behind
About Peter Larson
I’m having repeated problems with comments disappearing… hmm.. perhaps it is my browser or something, or that anything coming from Sweden is auto-classified as spam :-). Anyways, attempt two:
That shod running = heel-strike + overstride and barefoot/minimalist running = mid-foot/forefoot without overstride is a common association, and is statistically correct. However, you can run barefoot style with shoes, and some do. So I think when talking about injuries one should separate out what is running technique and what is related to shoes. It is great that you point out this in the post, because it is often mixed together.
“Shortening your stride” is a comparison to overstriding + heel-striking, which is extremely common in recreational runners. Barefoot running should not lead to a significantly shorter stride if you run correctly in shoes (possibly there is some slight difference anyway, due to shoes add some length due to the thickness of the sole). Oh, there’s one more difference, barefoot runner experts often teach lifting the foot actively to minimize friction forces in pushoff (to avoid blistering), while high performance shod running you want to focus on hip extension instead (I tend to think barefoot runners should do the same, would be interesting with some force platform analysis on these different styles, I suspect that you don’t gain much by lifting foot early). This active lift can shorten the stride.
What could problems be with taking shorter quicker strides?
Shorter quicker strides increases the number of times you stress the foot, which might be bad. That is for the same distance you will put down the foot more often. One theory I’ve seen is that this increase cancels out the advantage of reduced impact.
Landing closer to the CoG (which this “shortening of stride” really is about for 90% of the cases) will put higher load on your achilles/calf, which can be a problem, especially if you wear heel-toe-drop shoes in daily life so you have a shortened muscle. So injury can occur there if doing too much too soon. I believe in that runners should be just as picky when chosing everyday shoes as running shoes, to keep the feet and lower legs fit.
Barefoot running has a strong tradition on learning technique, while shod running has not. Would shod running be less injury prone if people learnt to run properly? Possibly. Another aspect of barefoot running is that it is a much stronger tradition to “listen to your body” and rest when needed etc. That tradition may also be significant contributor to why there may be less injuries.
I think it would be really interesting to further investigate if cushioning itself can lead to injury, that is look at the shoe factor not just the technique and training habit factors.
A theory (with some scientific support) around that is that with cushioning there is such poor ground feedback that the foot becomes less active before touchdowns / during support which can lead to problems. In other words, the cushioned shoe does not add to the foot’s ability to absorb impact, but rather replaces it and does a worse job.
We also have the instability factor, which can lead to exaggerated pronation, as discussed in my recent guest post.
The overall main theory however is that supportive shoe wearing may lead to that the foot becomes so weakened that it cancels out and overshoots the advantage of reduced impacts. That is a foot which is allowed to work with natural stresses and natural movement pattern will grow stronger to handle the icreased stress and in the end be less injury-prone than a foot encased in a supportive shoe. From a research point of view we do know that barefoot societies has considerably less injury problems. What we do not know is what happens if an adult which has used shoes for all life will ditch them, are the feet permanentely weakened or can they adapt? How large is the individual variations? We lack much knowledge in that area, but we gain more as the minimal/barefoot running community grows.
“I’m having repeated problems with comments disappearing… hmm.. perhaps it is my browser or something, or that anything coming from Sweden is auto-classified as spam :-).”
It’s not just Sweden! I had similar issues with a previous post and simply gave up.
Could be my commenting system – I’ll check into it.
Pete
Thanks for another excellent and thought provoking blog post.
Regarding Lieberman having identified some barefoot runners who heel strike, I believe that is an artifact of his subjects doing their running on the lab’s treadmill (all of which are partially cushioned). Regardless of the extent of cushioning present on Lieberman’s treadmills, however, his subjects certainly know that there is no risk on a treadmill for them to heel land on an unseen small pebble (an otherwise excruciating pain which would *quickly* revises the strike pattern of a neophyte barefoot runner subject to nature’s vagaries) the normal feedback mechanisms prompting running form changes are partially inhibited.
Regarding the initial awkwardness of running with a shorter stride, you’re absolutely right that *any* change feels that way until the neuro-muscular patterning becomes somewhat ingrained and the subject begins to see the benefit of their making the change. From my perspective, though the treadmill has the potential disadvantage of inhibiting running form changes, for a sincere runner interested in experimenting with their running form it makes an ideal test bed since without distraction of their environment they can concentrate fully on changes to their cadence, stride length, and overall running form, and how those elements affect their overall efficiency (measured indirectly by their respiration.) I have been doing exactly that over my repeated treadmill runs of late, while wearing minimal shoes such as the Nike Free Runs, Brooks running flats, and VFFs, and I think it’s paying off in my running form (i.e. a more rapid cadence of ~180 spm, a somewhat shorter stride, slight forward lean from my ankles, and landing closer to my COG). The jury is out until I have a chance to run competitively, but I’m very encouraged, so thanks again.
Mark,
It often goes unmentioned, but even some of the runners he filmed in Kenya
running barefoot did heel strike. This even includes 1 or 2 (can’t recall)
who had never worn shoes. Do you have the paper? If not, I can send you a
copy.
Pete
Great analysis, Pete. Interested in more of your thoughts once you get to read the study.
As I go longer into my marathon training one thing I’ve noticed is a perceptible difference in how my knees react during long runs. I’ve never had any real problems with them, but lately I can feel stress I haven’t before. I was wondering just the other day if it had anything to do with slowing down the pace, which would make sense since I’m no longer running as “light” as I normally do. All my weight is, theoretically, on those joints longer as my stride slows.
Just out of curiosity I’m going to see if I can determine what my current stride/minute rate is. When I started back running a few years ago I used to listen to BPM music, and for the most part was around 150-155. I know it’s much more now, but it will be interesting to see just how much.
Another great post and fantastic analysis, Pete. Keep up the good work.
You should try our running class. He will teach you how to run with proper form with more turn over and less time on the ground. You will be video taped before and after and get drills to take home.
I have switched to Vibrams and yes, I no longer suffer from knee pain, shin splints and it makes running fun again.
People who do experience problems are the ones that have been running for a while and then go out and do 3 miles in Vibrams thinking, the “start off slow” rule does not apply to them.
Well, I’m here to tell you, you have to start off slow. Maybe walk in them for a while, then build up to a mile and go from there.
I can’t imagine wearing my running shoes again.
Hi Pete,
I am really late in chiming in but I love this post and keep coming back to read it. One thing with Heiderscheit’s study is the limitations of link segment modeling. These only model external forces and incorporate any of the loading that occurs from muscular contractions. These variables could obviously impact the results and conclusions. And of course, we don’t know if greater forces are bad.
I thought you might like an article I just wrote summarizing the changes that occur with barefoot, shod and different footstrike positions. You have covered these areas extensively but I tried to add some of the research that is conflicting (which you have done as well) and might be a little lesser known.
If you ever want the original papers (in pdf) I can send them.
Here is the link
http://thebodymechanic.ca/2011…
Keep up the great writing,
Greg
Sorry to resurrect this from the dead, but I read with interest point 3 above. I am currently recovering from bone edema (2 of my metatarsals in the left foot). I began the shift to a midfoot strike, and was 6 weeks into the process when the pain began. I was so enthusiastic in the benefits of shifting from being a 7-yr heel striker that I tried a half-marathon about 6 weeks after starting the shift in my stability shoes with inserts! Had a great, fun run – faster cadence, increased speed, lesser of the braking effect.
I believe my thick-soled, insert-laden stability shoes were improperly matched to what I was doing. More of my “midfoot” strike was actually “forefoot” because I couldn’t feel the middle well. It was as if the shoes shifted my foot too far forward, especially for what they were prepared to do.
Had I actually a) not gone that far, and b) had a shoe with a lower toe-to-heel height, I most likely would not be sitting on the sidelines.
This said, thanks for all the information. I am learning a lot and have 2 different pairs of shoes to try when I get back to fulltime (and shorter distance) running!
I also seek to resurrect this from the dead. But I have runner’s knee and I have been taking new approaches for myself and my fellow athletes on how to reduce the knee pain and was wondering if any of this type of form spoken could help?
Increasing cadence could be an effective thing to try for runner’s knee, as well as maybe doing some work to increase gluteus medius strength if you have issues with hip stability.
I have tried multiple methods to fight the injury and have yet to find a resolution. What has been your worst injury and how did you overcome it?