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Re: Vibram Sued Over FiveFingers Claims
This is a great topic. Several comments.
I suggest some caution with regards to assuming higher joint stresses with minimalist shoes and barefoot running, as it depends on the joint and mode of mechanical transmission. I've been helping supervise a medical resident (PM&R) who had been collecting data in this area, and is planning new studies. Without giving too many details (manuscript recently submitted), in one study his teams' recent data from 2000 marathon runners who were classified by foot-strike and type of shoe shows that while just over 90% of marathon runners were heel strikers, the non-heel strikers were among the faster runners (p<.0001), and the non-heel strikers wore a variety of shoe types (but a higher proportion minimalist). There were no gender differences. While this is in part just documenting the obvious (e.g., watch slow-motion videos of championship runners like Usain Bolt and see the tremendous elastic recoil after the fore-landing), and applies to long distances as well (e.g., the male and female marathon record-holders and most of their colleagues run with ultra-ight-weight “racing flats” without the high-heels). And there are runners with foot-ankle prostheses that are tuned ankle-springs that are within a second or so of world records for sprints. In studies my colleague is about to start, 3D motion and EMG will be sampled from both types of runners, including during the later stages of a long run, to better understand subtle biomechanics including with fatigue.
In 1990 I edited a “Multiple Muscle Systems” book that included chapters by pioneers Neil Alexander, At Hof and Tom McMahon that viewed muscles in part as springs, and cited stretch-shortening cycle and Cavagna’s classic work on elastic bounce in the 60s and 70s. Most of these insights, documented so well for various animals and for runners of that era, was done before the current high-heeled running shoes hit the mass-market, back in the days where there were fewer runners and elastic recoil was there to be observed. (Certainly that’s how I ran barefoot on beaches in San Diego as a college student.) Such insights pretty much don't apply with heel-strikers – especially joggers who heel-brake-plop to never even store the potential elastic energy. It's pretty clear to me as a biomechanist and modeler that mechanical transmission is profoundly different for heel vs forefoot strike. Without the smoother energy storage and load distribution over time, the evidence suggests higher (not lower) peak stresses at the knee and hip joints for those who are strong heel-strikers. It is interesting that this thread comes when there is a parallel thread on stiffness.
Recently I have been going through the diverse adnd conflicting literature, and have been experimenting with running in both types of shoes (mine are even more minimalist than FiveFingers), trying to decide whether I should switch over for triathlons/runs this summer (I have a chronic knee issue (no PCL in one knee from soccer 15 years ago) that limits my distance to tri’s/runs with only ~5Ks and running to about 6-7 miles/wk). I clearly have less head-torso bounce and slightly bent knees at foot-land when I run with minimalist shoes and will naturally fore-land, while using the traditional high-heeled running shoes that I’ve run in for 30 years since a grad student, I find it awkward to strike with the forefoot, and I land roughly flat-footed or slightly heel. Interestingly, running is so much quieter with fore-landing as opposed to heel-smacking that I’ve accidently surprised people and dogs when coming from behind. My guess is that Bolt makes minimal noise when he runs, and certainly cats and other elastic-bounce locomotors are known for their quietness.
A “benefit” of being a mid-50s person is that while I still run OK (under 7-min miles and 21 min 5Ks), recovery is much slower, felt both afterward and the next morning. Swimming/cycling/kayaking tend not to cause such issues. So as a test, I’ve been switching off shoe types roughly each week, after several runs in each. The “results” so far are shockingly predictable, without no closure so far on what to use this summer. After a run with fore-landing in minimalist, I have predictably less (often no!) knee pain afterwards, a true shock, but also predictably some tenderness near the Achilles insertion and significant ankle (but not knee) stiffness the next morning. My guess is that both the peak and the shear forces at the TF plate of knee are less. Yet when going back to the high-heeled running shoes, my usual knee pain and sometimes mild hip pain or in the other knee is evident by 2 miles or so and I quit around 3, often limping slightly, and ibuprophen and glucosamine await – but not needed for the foot/ankle region. A classic tradeoff, of the type that PM&R docs, therapists and trainers need to better understand – and I need to for myself. But my dream of perhaps being able to run more frequently again as I age – and also minimize the risk of osteoarthritis - is tied to whether I can make a full switch to minimalist shoes and what I do believe is the more natural form of running (but not jogging, which is a newer phenomenon). But I can assume you that in any case, I won't join any lawsuit against these innovative companies.
Jack
This is a great topic. Several comments.
I suggest some caution with regards to assuming higher joint stresses with minimalist shoes and barefoot running, as it depends on the joint and mode of mechanical transmission. I've been helping supervise a medical resident (PM&R) who had been collecting data in this area, and is planning new studies. Without giving too many details (manuscript recently submitted), in one study his teams' recent data from 2000 marathon runners who were classified by foot-strike and type of shoe shows that while just over 90% of marathon runners were heel strikers, the non-heel strikers were among the faster runners (p<.0001), and the non-heel strikers wore a variety of shoe types (but a higher proportion minimalist). There were no gender differences. While this is in part just documenting the obvious (e.g., watch slow-motion videos of championship runners like Usain Bolt and see the tremendous elastic recoil after the fore-landing), and applies to long distances as well (e.g., the male and female marathon record-holders and most of their colleagues run with ultra-ight-weight “racing flats” without the high-heels). And there are runners with foot-ankle prostheses that are tuned ankle-springs that are within a second or so of world records for sprints. In studies my colleague is about to start, 3D motion and EMG will be sampled from both types of runners, including during the later stages of a long run, to better understand subtle biomechanics including with fatigue.
In 1990 I edited a “Multiple Muscle Systems” book that included chapters by pioneers Neil Alexander, At Hof and Tom McMahon that viewed muscles in part as springs, and cited stretch-shortening cycle and Cavagna’s classic work on elastic bounce in the 60s and 70s. Most of these insights, documented so well for various animals and for runners of that era, was done before the current high-heeled running shoes hit the mass-market, back in the days where there were fewer runners and elastic recoil was there to be observed. (Certainly that’s how I ran barefoot on beaches in San Diego as a college student.) Such insights pretty much don't apply with heel-strikers – especially joggers who heel-brake-plop to never even store the potential elastic energy. It's pretty clear to me as a biomechanist and modeler that mechanical transmission is profoundly different for heel vs forefoot strike. Without the smoother energy storage and load distribution over time, the evidence suggests higher (not lower) peak stresses at the knee and hip joints for those who are strong heel-strikers. It is interesting that this thread comes when there is a parallel thread on stiffness.
Recently I have been going through the diverse adnd conflicting literature, and have been experimenting with running in both types of shoes (mine are even more minimalist than FiveFingers), trying to decide whether I should switch over for triathlons/runs this summer (I have a chronic knee issue (no PCL in one knee from soccer 15 years ago) that limits my distance to tri’s/runs with only ~5Ks and running to about 6-7 miles/wk). I clearly have less head-torso bounce and slightly bent knees at foot-land when I run with minimalist shoes and will naturally fore-land, while using the traditional high-heeled running shoes that I’ve run in for 30 years since a grad student, I find it awkward to strike with the forefoot, and I land roughly flat-footed or slightly heel. Interestingly, running is so much quieter with fore-landing as opposed to heel-smacking that I’ve accidently surprised people and dogs when coming from behind. My guess is that Bolt makes minimal noise when he runs, and certainly cats and other elastic-bounce locomotors are known for their quietness.
A “benefit” of being a mid-50s person is that while I still run OK (under 7-min miles and 21 min 5Ks), recovery is much slower, felt both afterward and the next morning. Swimming/cycling/kayaking tend not to cause such issues. So as a test, I’ve been switching off shoe types roughly each week, after several runs in each. The “results” so far are shockingly predictable, without no closure so far on what to use this summer. After a run with fore-landing in minimalist, I have predictably less (often no!) knee pain afterwards, a true shock, but also predictably some tenderness near the Achilles insertion and significant ankle (but not knee) stiffness the next morning. My guess is that both the peak and the shear forces at the TF plate of knee are less. Yet when going back to the high-heeled running shoes, my usual knee pain and sometimes mild hip pain or in the other knee is evident by 2 miles or so and I quit around 3, often limping slightly, and ibuprophen and glucosamine await – but not needed for the foot/ankle region. A classic tradeoff, of the type that PM&R docs, therapists and trainers need to better understand – and I need to for myself. But my dream of perhaps being able to run more frequently again as I age – and also minimize the risk of osteoarthritis - is tied to whether I can make a full switch to minimalist shoes and what I do believe is the more natural form of running (but not jogging, which is a newer phenomenon). But I can assume you that in any case, I won't join any lawsuit against these innovative companies.
Jack
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