Does a More Natural Strike Pattern Help to Protect Barefoot Runners from Injury?

Barefoot running has become increasingly popular and has been purported to reduce injury risk. Barefoot running reduces loading at impact compared to shod, rearfoot strike running. This impact loading has been associated with numerous running related injuries, further strengthening the argument that barefoot running reduces injury risk. However, to date, there is no scientific evidence to support these claims about injury. Barefoot running encourages a forefoot strike pattern, in order to avoid painful heel strikes. Forefoot striking has been associated with a decreased injury incidence compared to rearfoot strikers, potentially due to the reduced impact loading. However, it is unknown how decreased impact loading and alternate footstrike patterns affect injury on the tissue level. This project aimed to examine injury risk, mechanics, and bone loading in barefoot runners compared to shod runners.

In Aim 1, barefoot running injury incidence was examined and compared to shod running injuries. Despite sustaining more injuries to the plantar surface of the foot, barefoot runners did incur significantly fewer musculoskeletal injuries compared with shod runners. However, no difference in injury rates was detected due to the reduced running volume in the barefoot group.

Aim 2 sought to examine differences in mechanics between shod rearfoot, midfoot, and forefoot striking, as they compare to barefoot running. Barefoot running was associated with impact mechanics, stride length and kinematics that may be protective against injury. Midfoot striking was associated with a similar stride length and kinematics, however impact loading was not reduced compared to barefoot running. This may indicate that the reduced impact loading observed in barefoot running may be related to increased sensory feedback.

Finally, the goal of Aim 3 was to examine tibial strains and strain rates between shod and barefoot running, to gain insight into injury mechanisms. Reduced strains and strain rates were observed in barefoot running. This may indicate that barefoot runners have a reduced risk of tibial stress fractures. In contrast, forefoot striking was associated with higher strains and strain rates, due to the early and rapid onset of the plantarflexor muscles.

This research is timely as an increasing number of runners are opting to run barefoot for the purported health benefits. By identifying injury rates and distribution of injuries among barefoot runners, clinicians can make better recommendations about barefoot running to their patients. Finally, information from the finite element model may help clinicians to direct runners to footstrike patterns that effectively disperse the load throughout the limb.

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Year

Entry

1989

Schaffler MB, Radin EL, Burr DB. Mechanical and morphological effects of strain rate on fatigue of compact bone. Bone. 1989;10(3):207-214.

2000

Rauh MJ, Margherita AJ, Rice SG, Koepsell TD, Rivara FP. High school cross country running injuries: a longitudinal study. Clin J Sport Med. 2000;10(2):110-116.

2006

Cappellini G, Ivanenko YP, Poppele RE, Lacquaniti F. Motor patterns in human walking and running. J Neurophysiol. June 2006;95(6):3426-3437.

2007

Taddei F, Schileo E, Helgason B, Cristofolini L, Viceconti M. The material mapping strategy influences the accuracy of ct-based finite element models of bones: an evaluation against experimental measurements. Med Eng Phys. 2007;29(9):973-979.

2006

Taddei F, Cristofolini L, Martelli S, Gill HS, Viceconti M. Subject-specific finite element models of long bones: an in vitro evaluation of the overall accuracy. J Biomech. 2006;39(13):2457-2467.