Ask the Practitioner: Barefoot Running - Why (or Why Not), What, How?
For this edition of Ask the Practitioner, we connected with Adam Daoud, an experienced runner and medical student, who while at Harvard worked extensively on research in the Skeletal Biology Lab. His website states, "My current research interest lies in investigating the ways in which the human body is suited particularly well for endurance running and determining why Homo sapiens possess such incredible endurance running capabilities." As a co-author of the studies cited below as well as work published in the journal Nature, Adam has narrowly focused in on the plusses, minuses, and implications of a growing trend among running enthusiasts, barefoot and / or minimally shod running. Have you ever wondered if barefoot running would be good for you? Read on for Adam's perspective......
rc: What are the potential benefits of barefoot running or running in minimalist shoes?
AD: I think that the biggest potential benefit of the barefoot style of running is reduced injury. The barefoot style of running that habitually barefoot and minimalist runners tend to use is a forefoot strike, landing on the outside ball of the foot before easing the heel down under the control of the calf muscles. This style of running minimizes the forces experienced at impact, which may help to avoid injury. Notice that this focuses less on what is under a runners’ feet and instead considers how footwear affects how runners use their feet and how this changes their style of running. My recent work looking at foot strike and injuries in collegiate runners found a nearly two-fold reduction in running injuries among forefoot strikers, none of whom were barefoot runners (Daoud AI et al. Foot Strike and Injury Rates in Endurance Runners: a retrospective study. MSSE, 2012.). This was a study about running form, more work especially prospective work needs to be done to look at the interplay between footwear, running form and injury. A singular focus on what runners strap to their feet can easily lead a runner into danger.
Another potential benefit would be financial savings. Since forefoot strike runners do not use the cushioning of a shoe to reduce the impact, shoes can be worn for many more miles before being replaced. As a forefoot strike runner, I usually wait until the upper is pulling off the lower before tossing shoes.
Studies on running efficiency have gone both ways. Our lab recently found that running in minimal shoes is more efficient regardless of foot strike and that there was no difference between heel striking and forefoot striking in terms of running efficiency (Perl DP et al. Effects of Footwear and Strike Type on Running Economy. MSSE, 2012.). While Rodger Kram’s lab has found that barefoot running is less efficient than running in lightweight, cushioned shoes (Franz JR et al. Metabolic Cost of Running Barefoot versus Shod: Is Lighter Better? MSSE, 2012.). But in general, a less injured runner is a better-trained, fitter runner so even if forefoot striking is not more efficient there may be performance gains by avoiding time off due to injury.
rc: What are the risks?
AD: While the major benefit of the forefoot strike running is injury reduction, the greatest risk is increased chance of injury during a runner’s transition from their current running form to forefoot strike running and possibly doing so in a more minimal shoe. Forefoot strike running puts very different stresses on the lower limb compared to heel striking. The muscles of the calf and foot have to do more work each time the foot strikes the ground while the bones of the foot incur impact and bending forces that are different than those experienced in heel striking. In addition, running barefoot or in a more minimal shoe will require increased muscle force to stiffen the arch of the foot and the bones of the foot may be subjected to less evenly distributed forces. Recent case reports have described instances of metatarsal injury in runners transitioning to barefoot running. Though if case reports were written up for all of the injuries sustained by “normal” runners, sports medicine journals wouldn’t have room for anything else.
Other risks are quite obvious such as injury to the sole of the foot due to surface conditions if a runner chooses to run completely barefoot. Though these risks can be greatly reduced by using your eyes and choosing smooth surfaces that are free of jagged debris. A hard surface such as a road or sidewalk can be a good surface.
rc: What are some sensible ways to experiment with barefoot / minimalist running to explore whether it is appropriate for you?
AD: The first thing to do is to decide whether or not your current form is working for you. If in your years, possibly decades of running you’ve found shoes that fit your running form and you’re not plagued by injuries then why change? But if you’ve struggled with injury as a heel strike runner then you might want to consider trying out forefoot striking. Unless they ask, my running friends don’t hear a word from me about running form until they get injured. This not only gives me a chance to figure out how much they’ve been injured in the past, but also transitioning to forefoot strike running can line up perfectly with returning from injury since you’re already running at a reduced volume and intensity. Transitioning should be done slowly and in accordance with what your body is telling you, just as you would any other new training technique such as weightlifting or plyometric exercises.
Concerning form, jump straight up in the air. Where on your foot did you just land? You should do the same when you run. Try out running completely barefoot on a track or smooth paved surface to try to get a feel for what it should feel like. Your bare feet will encourage you to run correctly as it will hurt to do otherwise. Don’t run barefoot on overly soft ground to learn good technique since the cushioning of the ground will allow you to run without good form. You can find more information including videos of forefoot strike running in various footwear on my past lab’s website.
The biggest mistake a runner could make would be to buy the newest, coolest pair of minimalist shoes and then go out and continue running in the same way they always have – heel striking – in their new minimal shoes. The heel cushioning of a standard running shoe will no longer attenuate the large impact forces of heel striking. Another mistake would be to consider the barefoot style as a panacea and to suddenly switch 100% of your running to forefoot striking. Your muscles need time to grow stronger and to learn the new firing pattern of a new gait pattern. And your bones need time to strengthen and remodel to adequately deal with the new loading patterns of forefoot strike running.