Asymmetry Changes During Distance Running in Recreational Runners

Date

2024

Authors

Smith, Kayla

Journal Title

Journal ISSN

Volume Title

Publisher

University of Oregon

Abstract

Bilateral asymmetry is a difference in shape, size, and form on two sides of a given axis (Maloney et al., 2019). As fatigue increases during running, there is greater metabolic energy cost and lower mechanical efficiency (Mizrahi et al., 2000) which may be associated with increased asymmetry. This study aimed to determine asymmetry changes between right and left foot peak accelerations and at the sacrum during an outdoor run. Twenty-four runs from 8 participants (5F/3M) training for either a half marathon or a marathon were analyzed. Participants wore inertial measurement units and ran self-selected routes (13.7±4.5 mi) and pace (9:24±1:10 min/mi). Asymmetry was calculated using symmetry angle expressed as a percentage, where 0% is perfect symmetry (Zifchock et al., 2008). Runs were grouped into lower mileage (<13.5 mi) or higher mileage (>13.5 mi) groups and symmetry angle was averaged over quarters of each run. Significance was tested for using a one-way ANOVA. Symmetry angle was not significantly different over quarters of lower mileage group or higher mileage group runs or between groups. However, there was a trend in all runs of average symmetry angle increasing at the feet during each quarter. Additionally, average symmetry angle tended to be larger in the higher mileage group compared to the lower mileage group. Samples showed great variance in symmetry angle size indicating that individual participants may have significant changes in asymmetry. Understanding running mechanics in the natural running environment can provide useful insight into running technique and injury prevention.

Description

Keywords

Asymmetry changes, Recreational runners, Distance running, Symmetry angle, Peak acceleration

Citation