Minimalist Shoes, is it Worth the Switch?
Inherently the fitness industry is subject to trends, as exercise enthusiasts tend to gravitate toward novel products and activities. Not surprisingly, when the minimalist trend in shoe wear hit the retail stores many runners and cross trainers quickly hopped on the bandwagon. The popularity of the new shoe features created a rapid market shift with minimalist shoes now making up 15% of the $6.5 billion running shoe market. And although wildly popular, experts suggest that the shoes come with a warning label.
According to researchers from BYU, the "barefoot" style of shoes need an acclimation period, and possibly not all individuals are candidates for the five-finger running shoes. A new study from the journal, Medicine & Science in Sports & Exercise (2013) found that runners who make too rapid of a transition to minimalist shoes suffer an increased risk of injury to bones in the foot, including possible stress fractures.
According to Sarah Ridge, study lead author and assistant professor of exercise science at BYU, "Transitioning to minimalist shoes is definitely stressful to the bones, you have to be careful in how you transition and most people don't think about that; they just want to put the shoes on and go."
The research examined 36 experienced runners over a 10-week period. Prior to the study, each runner underwent MRIs to evaluate the architecture of their feet. Half of the runners were then asked to gradually transition into five-finger minimalist shoes while the other half continued to run in traditional running shoes. Subjects in the experimental group followed an industry suggested protocol. They performed one short (1-2 mile) run in the minimalist shoes the first week, and added an additional short run each week so that they ran at least 3 mile distances in the new shoes by the third week. They were then instructed to add mileage in the minimal shoes as they felt comfortable, with the goal of replacing one short run per week in traditional shoes with the new shoes.
The researchers conducted MRIs on the runners’ feet for a second time at the end of the 10-week period. The scans revealed that those who had transitioned to the minimalist shoes suffered greater increases in bone marrow edema (inflammation causing excessive fluid in the bone) and an increase in stress injuries compared to those wearing traditional running shoes.
"Whenever a bone is impacted by running (or some other repetitive action), it goes through a normal remodeling process to get stronger," Ridge said. "Injury occurs when the impact is coming too quickly or too powerfully, and the bone doesn't have a chance to properly remodel before impact reoccurs."
Interestingly, the study found the runners who experienced the majority of stress injuries were women. The research team concluded that if minimalist shoes are to be used for running, they should be used very gradually as even 10 weeks seems to be insufficient for acclimation among some individuals. Likewise, runners using minimalist shoes may want to employ lower volumes to further reduce the risk for foot injuries.
According to Johnson, a co-author on the study, "People need to remember they've grown up their whole life wearing a certain type of running shoes and they need to give their muscles and bones time to make the change. If you want to wear minimalist shoes, make sure you transition slowly." The investigators plan to follow-up with the study in an effort to begin establishing clear recommendations for anyone considering making the switch.