Lower limb kinematic variability associated with minimal footwear during running

Abstract

Purpose: This study investigated lower limb variability when trained runners wore a minimal shoe for the first time. It was hypothesised that initial lower limb variability would be decreased in the minimal shoe condition due to lack of familiarity. It was also hypothesised that variability would increase over time as runners become more familiar with the condition.

Methods: Testing included three 10 minute treadmill running trials conducted in runner's own running shoes, a pair of minimal shoes followed by runner's own shoes again. The shoe order was selected so as to establish a baseline value of variability in a runner's most familiar shoes followed by a perturbation which was the inclusion of minimal shoes. Continuous Relative Phase (CRP) relationships and kinematic values at heel strike were determined which allowed lower limb variability to be quantified.

Results: Kinematic variability values were not statistically different between runner's own shoes and minimal shoes. CRP relationships did not differ between minimal shoes and runner's own shoes or over time.

Conclusions: Trained runners did not change lower limb variability while wearing minimal shoes for the first time. Lack of familiarity does not appear to affect lower limb variability. The footwear included in this research study had similar cushioning properties to traditional footwear but with a different construction which may relate to similar values found between conditions. Investigating how runners of different abilities transition to minimal footwear should be focused upon to reduce risk of injury.

Keywords:

• minimal footwear
• running
• kinematic variability
• continuous relative phase
• running adaptation

Acknowledgements

The authors would like to thank NSERC, the Nike Sport Research Lab for supplying the minimal footwear and Glynnis Pardo for assistance in data processing.