By Jordana Bieze Foster
The biomechanical differences between barefoot running and running in minimalist shoes appear to amount to more than just a matter of time.
In a session on barefoot and minimalist running at the annual meeting of the American College of Sports Medicine (ACSM) in late May, two presentations offered conflicting evidence as to whether runners who switch to minimalist shoes immediately adopt the type of mechanics associated with barefoot running. Three other studies presented in the same session, however, found that even runners experienced in minimalist running had mechanics that differed significantly from those associated with barefoot running.
In 10 recreational runners who had no previous experience with minimalist or barefoot running, researchers from Utah Valley University in Orem found that switching from a traditional shoe to a zero drop shoe, a minimalist shoe, or bare feet resulted in acute significant decreases in soleus and tibialis anterior muscle activity that were similar for all three nontraditional shoe conditions.
Previous studies have demonstrated that habitual barefoot running is more often associated with a midfoot or forefoot strike pattern than the rearfoot strike pattern that is typically associated with running in traditional shoes; minimalist shoes are also thought to promote a nonrearfoot strike pattern. But, in 21 runners who demonstrated a rearfoot strike pattern in traditional shoes, researchers from Brigham Young University (BYU) in Provo, UT, found that 16 did not change their foot strike pattern immediately after switching to minimalist shoes. They also found that changes in foot strike angle were more pronounced when switching from traditional shoes to barefoot than when switching to minimalist shoes.
The BYU foot-strike findings contrast with those of a recent Footwear Science article, in which 65% of 40 habitual rearfoot strikers switched to a nonrearfoot strike pattern when asked to run barefoot on a hard surface.
Most experts agree that outside the laboratory, runners should not make an abrupt switch from traditional shoes to either minimalist shoes or barefoot running, instead transitioning gradually over time. A popular assumption is that during the transition, the runner’s mechanics will evolve to more closely resemble those of habitual barefoot runners. But research presented at the ACSM meeting suggests that may not be the case, at least for the transition to minimalist shoes.
In 22 endurance runners with no previous experience with nontraditional running, researchers from Stellenbosch University in South Africa found no significant kinematic or kinetic differences between those who underwent seven weeks of minimalist-shoe training and those who continued to wear their usual shoes. They also found some surprising changes in foot strike pattern in the minimalist-shoe group.
“At the beginning, most of them were midfoot strikers in the minimalist shoes, although it was very variable. But what we tended to see at the post-test was that a lot of them shifted slightly more toward the heel,” said Kurt Schütte, a biokineticist in the university’s Movement Laboratory, who presented the findings at the ACSM meeting. “This was the opposite of what we expected. Calf soreness was still an issue at that point, so maybe the shift toward the heel was an attempt to alleviate that discomfort.”
Of 11 experienced minimalist-shoe runners, researchers from the US Army Research Institute of Environmental Medicine in Natick, MA, found that seven were rearfoot strikers. And in eight runners with at least two years experience in minimalist shoes, researchers from Massachusetts General Hospital in Foxborough, MA, found that six were still running with a rearfoot strike pattern.
“This tells us that people would probably benefit from more education to get what they’re aiming for in terms of a barefoot-like running experience,” said Donna M. Scarborough, MS, PT, clinical and research director of the Mass General Sports Performance Center in Foxborough, who presented her group’s findings at the ACSM meeting.
Bohne M, Roach K, Allphin N, et al. Electromyographical analysis of barefoot, minimalist, zero-drop, and standard running shoes. Presented at the 60th American College of Sports Medicine annual meeting, Indianapolis, May 2013.
Nelson J, Hunter I, Mitchell U, et al. The effect of footwear on foot strike patterns in running. Presented at the 60th American College of Sports Medicine annual meeting, Indianapolis, May 2013.
Gruber AH, Silvernail JF, Brueggemann P, et al. Footfall patterns during barefoot running on harder and softer surfaces. Footwear Sci 2013;5(1): 39-44.
Schütte KH, Venter RE. The effect of minimalist shoe training on lower limb kinematics and kinetics. Presented at the 60th American College of Sports Medicine annual meeting, Indianapolis, May 2013.
Fellin RE, Seay JF, Hill RD, et al. Differences in running mechanics and strength between runners in minimalist and traditional footwear. Presented at the 60th American College of Sports Medicine annual meeting, Indianapolis, May 2013.
Scarborough DM, Driscoll S, Salzer M, Berkson EM. Comparison of the biomechanics of running in barefoot and minimalist shoe conditions. Presented at the 60th American College of Sports Medicine annual meeting, Indianapolis, May 2013.