Running stiffness and spatiotemporal parameters are similar between non-runners and runners with different experience...

Spatiotemporal parameters and leg and joint stiffness are variables that represent the fundamental dynamics of running. Therefore, these variables may effectively differentiate between less-experienced and more-experienced runners' gait, possibly addressing differing injury rates between populations. We compared stiffness and spatiotemporal parameters between runners with different experience levels, including a group with no previous running experience. Healthy physically active participants (22.1 ± 3.6y) were divided into three groups, according to experience: experienced (running >1-year, 14-48 km/week; n = 23, 9F), novice (running <1-year, 5-21 km/week; n = 15, 4F) and non-runners (no running for the past 5 years; n = 17, 7F). Three-dimensional motion capture and force plates measured gait mechanics during overground running at 3.35 m·s^-1. Knee, ankle and three-dimensional leg stiffness, contact time, flight time and step length were compared between groups using independent-measures ANCOVA (covariate = sex). No biomechanical variable was significantly different between the groups (leg: p = 0.652, Hedges' g = 0.09-0.17; ankle: p = 0.439, g = 0.07-0.19; knee: p = 0.153, g = 0.13-0.29; contact time: p = 0.592, g = 0.06-0.24; flight time: p = 0.513, g = 0.03-0.40; step length: p = 0.107, g = 0.26-0.61). Stiffness and spatiotemporal parameters were not different between runners with greater than 1-year of experience when compared to runners with less than 1-year experience and non-runners. Therefore, running gait may not differentially affect injury rates between experience levels.