Abstract
During the ground contact phase of running, the body’s mass is rapidly decelerated
resulting in forces that propagate through the musculoskeletal system. The repetitive
attenuation of these impact forces is thought to contribute to overuse injuries. Modern
running shoes are designed to reduce impact forces, with the goal to minimize running
related overuse injuries. Additionally, the fore/mid foot strike pattern that is adopted
by most individuals when running barefoot may reduce impact force transmission. The
aim of the present study was to compare the effects of the barefoot running form (fore/mid
foot strike & decreased stride length) and running shoes on running kinetics and impact
accelerations. 10 healthy, physically active, heel strike runners ran in 3 conditions:
shod, barefoot and barefoot while heel striking, during which 3-dimensional motion
analysis, ground reaction force and accelerometer data were collected. Shod running
was associated with increased ground reaction force and impact peak magnitudes, but
decreased impact accelerations, suggesting that the midsole of running shoes helps
to attenuate impact forces. Barefoot running exhibited a similar decrease in impact
accelerations, as well as decreased impact peak magnitude, which appears to be due
to a decrease in stride length and/or a more plantarflexed position at ground contact.
Key words
biomechanics - locomotion - heel strike - running - footstrike - impact
