Written By Barefoot Dawsy
Honestly, I think that there was a case against them, and that they may have been premature about making claims about injury prevention. However, there is one part of the case which has me fuming, and which is conveniently the core argument of most of the articles I’ve read. Note: I’m not going to link to any of these articles here, but Google “Vibram Class Action” if you haven’t read about the case yet.
What I’m referring to is the now famous Foot Bone Marrow Edema after 10-Week Transition to Minimalist Running Shoes (pdf) study published by the journal Medicine & Science in Sports & Exercise. Every article that I’ve read so far about this issue has held this study up as proof-positive that Vibram Five Fingers (VFF) are the devil’s work, and will cause severe injury to anyone who tries a pair on.
Having actually read the report, I find it surprising that anyone would use it as the basis for an argument, let alone a court case. Though it was carried out by a reputable organisation, with good intentions and, for the most part, careful measurements, in truth, the study falls down in several areas:
- Sample Size: There were 36 participants at the start of the study. 10 of these were used as a control group, meaning that only 19 runners were wearing Vibrams. This is a tiny sample size, which could very easily cause statistical anomalies to corrupt the results.
- Runner choice: The participants (men and women) were all running 15-30 miles per week for 6 months prior to the study. This shows that each runner was likely quite experienced, and probably used to a particular style of running. Transitioning to a new strike style for this group may have been more likely to cause injury than for runners with different levels of ability, especially beginners.
- Unclear Transition Instructions: The study claims to have used the transitioning guidelines published on the Vibram website in 2011 (or 2010, depending on where in the study you look). Unfortunately, these are not described, and not correctly/adequately cited. We don’t know what the guidelines were, so it’s hard to assess if they were followed correctly.
- Concurrent Running in Regular Shoes: As per the study, participants in the VFF group were also running most of their mileage wearing regular running shoes. It’s pretty difficult to determine whether or not the use of VFFs is the cause of the reported injuries, or the combination of VFFs and running. Eg it can’t be ruled out that a hybrid transitional period is more detrimental than a cold-turkey approach.
- Runner Nationality: From what I can tell, the participants in this study were all Haitians, and I assume the study took place in Haiti. There don’t appear to be any concessions made to the runners’ nationalities. The study cannot conclusively show that the injuries demonstrated are not exclusive to the Haitian population. Unlikely, sure, but there are significant differences in diet, fitness levels, environment between Haiti, and America or Australia.
- Uncooperative Participants: The participants of the study were required to record their progress in a journal, detailing their mileage in and out of VFFs. However, as the study states, “this did not happen for the majority of subjects“. A study is not a study when the subjects are not adequately supervised or their progress recorded. There have been several studies in the past that have made this same error, and IMHO it completely invalidates the research being performed.
What really worries me though is not the study so much as the media/blogosphere beatup that ensued. The study concludes with:
Thus, to minimize the risk of bone stress injury, runners who want to run in VFF should transition over a longer duration than 10 weeks and at a lower intensity (miles per week) than the subjects in this study
That seems to me a fair conclusion given the results of the study. Note that it is not said that VFFs are inherently dangerous or that running in them will always cause injury. As Vibram and countless others have done, the study recommends patience and prudence, building up mileage slowly and not pushing too hard. Sound familiar?
Studying running, and especially, it would seem, barefoot running, is tricky work. There are thousands of variables to be taken into consideration. There are ways of going about it, but unfortunately, this requires money, time, and willing participants, all of which seem sorely lacking.
What we need to do in the meantime, however, is look past the sensationalist claims of both sides of the argument, and do our best to make sensible choices. The jury’s still well and truly out on the barefoot/minimalist vs Big Shoe (you like that? I just made it up), so until we get at least 1 decent study (please!), we’re left to work it out for ourselves.
Ultimately, when making any major change in life, it’s important to do your homework, tread carefully and take responsibility for your actions. Anyone that’s taken up barefoot/minimal running since 2009 has no excuse for not educating themselves and learning about the risks of transitioning, which have been widely cautioned against.
So remember, take your time, listen to your body, and learn your limits. Switching from bulky sneakers to minimal shoes or barefoot is a big adjustment that shouldn’t be treated lightly. We’ve spent years getting accustomed to running around with marshmallows on our feet, and for most people it will take a long time to fix that.