Segment Coordination Variability Differs by Years of Running Experience

: Running is a popular activity that results in high rates of overuse injury, with less-experienced runners becoming injured at higher rates than their more-experienced peers. Although measures of joint kinematics and kinetics and ground reaction forces have been associated with overuse running injuries, similar differences across levels of running experience have not been found. Because running is a motor skill that may develop with experience, an analysis of segment coordination and its variability could provide additional insight into why injury incidence decreases with increasing experience. PURPOSE: The purpose of this study was to determine if less-experienced runners have different segment coordination and lower segment coordination variability compared with their more-experienced peers. METHODS: This retrospective analysis included 20 more-experienced (≥10 yr running) and 21 less-experienced (≤2 yr running) runners. Sagittal thigh versus shank and shank versus foot segment coordination and coordination variability were calculated using a modified vector coding approach as individuals ran on a treadmill at preferred pace. Coordination and its variability were compared between groups during terminal swing and early, mid, and late stance for both segment couples. RESULTS: Segment coordination was similar between less- and more-experienced runners. Less-experienced runners had lower segment coordination variability compared with more-experienced runners for both the thigh versus shank and shank versus foot couples. This lower variability occurred during early and mid stance. CONCLUSIONS: Runners appeared to attain stable segment coordination patterns within 2 yr of consistent running, but had lower coordination variability compared with individuals who had been running for 10 or more years. These results suggest that assessment of movement patterns and their flexibility may help inform injury prevention or treatment strategies for less-experienced runners.