A few years ago if anybody mentioned ‘barefoot running’ it may have evoked images of rail-thin East Africans, legendary South African runner Zola Budd, or if you are old enough, British runner Bruce Tulloh. Fast forward to 2014 and most people discussing barefoot running (BFR) make an immediate association with the ‘funny toe shoes’ that effectively combine true barefoot running with the recent minimalist running shoe craze.
BFR is naturally closely linked to the polarising debate around forefoot vs. heel striking and most recently Vibram, the maker of the aforementioned FiveFingers shoes, settled a US$3.75m class action lawsuit for deceptive marketing, by claiming that their shoes could strengthen foot muscles while reducing running injuries.
How did we get to this point so quickly?
Modern ‘jogging’ as we know it has only been around for 50 years, with BFR gaining popularity in the last 10. The majority of current research on running injuries seems quite inconclusive as regards the pros and cons of BFR.
What Does The Science Say?
- Broad support of the concept of BFR would be Michael Warburton’s retrospective review Barefoot running1 of past research in which he found:
- Running related injuries to bone and connective tissue in the legs are rare in developing countries where most runners are unshod
- Where both barefoot and shod populations exist (Haiti), injury rates of the lower extremity are substantially higher in the shod population
- Footwear can increase the risk of ankle sprains
- Plantar fasciitis is rare in barefoot populations
- Running barefoot reduces oxygen consumption by a few percents.
In 2010, Daniel Lieberman pointed out that barefoot runners with a mid-foot to forefoot strike generate smaller collision forces, markedly less than heel striking, shod or unshod, attributed to a more plantar-flexed position and better shock absorption through the ankle and foot2. In the spring of 2012, Lieberman published a summary of BFR type research and concluded that “we simply do not know yet” the influence of BFR on injury risk3.
A few weeks later Lieberman published what appears to be the first evidence that natural, forefoot running (a byproduct of BFR) causes significantly less risk of repetitive stress injury than those who heel strike. In the study, heel strikers showed 2.6 x more chance of injury and 3-4% less efficiency than forefoot strikers. A study by Hansen et al. (2012) went on to show that when tested on a treadmill BFR is only 2% more economical, but it was 5.7% more economical when tested outdoors on the ground. Even more seemingly conclusive results were found by Perl et al. (2012) where minimally shod runners came off being significantly more economical than regularly shod runners regardless of the type of foot strike4.
At the 2012 meeting of the American College of Sports Medicine, three studies were presented by DePaoli et al., Michigan’s Adrian College and by Altman et al. Their research showed that runners on a treadmill were faster and more economical but also had higher rates of injury during the transition phase to BFR. Altman’s internet survey of 109 runners making the transition to BFR had 18 runners reporting muscle or bone injuries and 16 with an injury to the bottom of the foot.
Contrary to what we have just read about the benefits of BFR, a late 2000s University of Newcastle review effectively damned sports shoes in general when it came to injury prevention, finding no published research at all that showed a relationship between injury prevention and using motion control shoes or shoes with large high cushioned heels. Many extended this finding to minimalist shoes being unable to live up to their grandiose claims of injury prevention.
Confusingly, a 2013 study in the Journal of Applied Physiology5 showed 19 heel strikers were more economical by a considerable margin when measured on a treadmill over 18 forefoot strikers. Even more incredibly, when the forefoot strikers then tried to heel strike, they tested more economical than their habitual forefoot style. The study concluded that heel strikers burned fewer carbs and used more from fat and other sources, thus postponing ‘hitting the wall’ when all the body’s glycogen stores were depleted.
In the same year, a 2013 Brigham Young University study tested whether BFR strengthened the foot, believing that if the foot muscles did indeed get stronger then the arch would rise and could be measured. Putting their runners through a 10-week minimalist shoe trial, they found no significant gains in arch height6. Another survey of 566 runners asked if they had tried to transition to BFR, and of the one third that had tried, 32% had suffered injuries and switched back to their old form of running.
By the 2014 meeting of the American College of Sports Medicine, five research presentations showed absolutely no significant benefits in terms of running economy for BFR over conventional shoes. One researcher went so far as to take photos of the moment of foot strike for 50 distance runners at the US Olympic trials, with the photos capturing every possible strike position from solid heel strikes to mere baby toe strikes.
Is it for you?
When patients ask me whether they should try barefoot running, my first question is ‘why?’ – if it ain’t broke, don’t fix it. Everybody has different biomechanics and thus BFR may not be suitable for you, so really question what it is about it that appeals.
I often highlight two things that will help with barefoot success:
- You were born in the Rift Valley
- You spent a good portion of your life running barefoot.
What I see all too often with runners interested in BFR are increased injuries when the transition is done too quickly, mostly due to too many different elements in running style needed to change for a successful transition. BFR is at one extreme end of the current shoe spectrum, so you must be prepared to move to a ‘zero drop’ (flat from toe to heel) and zero cushioning shoe. This involves changing your foot strike pattern, stride length, stride frequency, body position and also different demands on your musculature.
As we have seen, the research is mixed and inconclusive and it’s hard to compare the evidence in areas of injury prevention, running efficiency and body posture, so why make the switch? It’s not as simple as X causes Y, and yet many of the studies put all the focus of injury on shoe or foot strike when a myriad of other things also come into play. Given time and better research, we may yet see that BFR has distinct advantages over other styles of running. As it is a newer trend to the global running world, I don’t feel justified in making any sweeping statements, but I certainly feel some of Vibram’s claims may indeed be proved correct, given time.
Article by Dough Tahirali
1 Warburton, M (2001) Barefoot running. Sportscience 5:1-4.
2 Lieberman, DE et al. (2010) Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature 463: 531-535.
3 Lieberman, DE (2012) What we can learn about running from barefoot running: an evolutionary medical perspective. Exercise and sport sciences reviews, 40: 63-72.
4 Daoud, AI et al. (2012) Foot strike and injury rates in endurance runners: a retrospective study. Med Sci Sports Exerc, 44:1325-34.
5 Gruber, AH (2013) Economy and rate of carbohydrate oxidation during running with rearfoot and forefoot strike patterns. Journal of Applied Physiology, 115:194-201.
6 Ridge et al. (2013) Foot bone marrow edema after 10-week transition to minimalist running shoes. Med Sci Sports Exerc, 45:1363-8.