title: Association of previous injury and speed with running style and stride-to-stride fluctuations.
abstract: Running-related injuries remain problematic among recreational runners. We evaluated the association between having sustained a recent running-related injury and speed, and the strike index (a measure of footstrike pattern, SI) and spatiotemporal parameters of running. Forty-four previously injured and 46 previously uninjured runners underwent treadmill running at 80%, 90%, 100%, 110%, and 120% of their preferred running speed. Participants wore a pressure insole device to measure SI, temporal parameters, and stride length (S(length)) and stride frequency (S(frequency)) over 2-min intervals. Coefficient of variation and detrended fluctuation analysis provided information on stride-to-stride variability and correlative patterns. Linear mixed models were used to compare differences between groups and changes with speed. Previously injured runners displayed significantly higher stride-to-stride correlations of SI than controls (P = 0.046). As speed increased, SI, contact time (T(contact)), stride time (T(stride)), and duty factor (DF) decreased (P < 0.001), whereas flight time (T(flight)), S(length), and S(frequency) increased (P < 0.001). Stride-to-stride variability decreased significantly for SI, T(contact), T(flight), and DF (P ≤ 0.005), as did correlative patterns for T(contact), T(stride), DF, S(length), and S(frequency) (P ≤ 0.044). Previous running-related injury was associated with less stride-to-stride randomness of footstrike pattern. Overall, runners became more pronounced rearfoot strikers as running speed increased.
authors.affiliation: Sports Medicine Research Laboratory, Public Research Centre for Health, Luxembourg, Luxembourg.|NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Mann
authors.affiliation: Sports Medicine Research Laboratory, Public Research Centre for Health, Luxembourg, Luxembourg.
authors.forename: L
authors.initials: L
authors.lastname: Malisoux
authors.affiliation: Sports Clinic, Centre Hospitalier de Luxembourg, Luxembourg, Luxembourg.
authors.forename: C
authors.initials: C
authors.lastname: Nührenbörger
authors.affiliation: Sports Medicine Research Laboratory, Public Research Centre for Health, Luxembourg, Luxembourg.|Sports Clinic, Centre Hospitalier de Luxembourg, Luxembourg, Luxembourg.
authors.forename: A
authors.initials: A
authors.lastname: Urhausen
authors.affiliation: NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Meijer
authors.affiliation: Sports Medicine Research Laboratory, Public Research Centre for Health, Luxembourg, Luxembourg.
authors.forename: D
authors.initials: D
authors.lastname: Theisen
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D005080:Exercise Test; D005260:Female; D005528:Foot / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012420:Running / Q000293:injuries* / Q000502:physiology*; D014160:Transducers, Pressure
keywords: Strike index; detrended fluctuation analysis; running biomechanics; running-related injury