Just because a runner’s foot strike pattern changes as a result of switching from shod to barefoot running doesn’t necessarily mean that runner will experience lower impact loading rates, according to research from the University of Oregon presented in August at the ASB meeting.

Investigators analyzed vertical impact loading rates (VILR) in 20 habitually shod runners as they ran at self-selected speeds under shod and barefoot conditions. Of the 40 feet, the researchers found that foot strike pattern was predictive of VILR for just five feet under each condition.

Further analysis revealed that, in the runners who did switch from a rearfoot to a forefoot or midfoot strike pattern when switching from shod to barefoot running, the effect on loading rate was highly variable. In fact, the VILR increased in most cases, according to James Becker, MS, a doctoral candidate in the Motion Analysis Laboratory at the university who presented the findings.

“Claims regarding the relative merits of one foot strike pattern versus another should be interpreted with caution, because it’s really dependent on the individual,” Becker said.