Background: Lack of an observable vertical impact peak in fore/mid-foot running has been suggested as a means of reducing lower extremity impact forces, although it is unclear if impact characteristics exist in other ...Background: Lack of an observable vertical impact peak in fore/mid-foot running has been suggested as a means of reducing lower extremity impact forces, although it is unclear if impact characteristics exist in other axes. The purpose of the investigation was to compare three-dimensional(3 D) impact kinetics among foot-strike conditions in over-ground running using instantaneous loading rate–time profiles.Methods: Impact characteristics were assessed by identifying peak loading rates in each direction(medial–lateral(ML), anterior–posterior(AP),vertical, and 3 D resultant) following foot-strike instructions(fore-foot, mid-foot, subtle heel, and obvious heel strike). Kinematic and kinetic data were analyzed among 9 male participants in each foot-strike condition.Results: Loading rate peaks were observed in each direction and foot-strike condition, differing in magnitude by direction(3 D resultant and vertical > AP > ML, p ≤ 0.031) and foot-strike: ML(fore-foot and mid-foot strike > obvious heel strike, p ≤ 0.032), AP(fore-foot and mid-foot strikes > subtle-heel and obvious heel strikes, p ≤ 0.023). In each direction, the first loading rate peak occurred later during heel strike running relative to fore-foot(p ≤ 0.019), with vertical and 3 D resultant impact durations exceeding shear(ML and AP, p ≤ 0.007) in each condition.Conclusion: Loading rate–time assessment identified contrasting impact characteristics in each direction and the 3 D resultant following foot-strike manipulations, with potential implications for lower extremity structures in running.展开更多
基金funded by the Institutional Development Award Network of Biomedical Research Excellence through the National Institute of General Medical Sciences (8 20 GM103440-11)
文摘Background: Lack of an observable vertical impact peak in fore/mid-foot running has been suggested as a means of reducing lower extremity impact forces, although it is unclear if impact characteristics exist in other axes. The purpose of the investigation was to compare three-dimensional(3 D) impact kinetics among foot-strike conditions in over-ground running using instantaneous loading rate–time profiles.Methods: Impact characteristics were assessed by identifying peak loading rates in each direction(medial–lateral(ML), anterior–posterior(AP),vertical, and 3 D resultant) following foot-strike instructions(fore-foot, mid-foot, subtle heel, and obvious heel strike). Kinematic and kinetic data were analyzed among 9 male participants in each foot-strike condition.Results: Loading rate peaks were observed in each direction and foot-strike condition, differing in magnitude by direction(3 D resultant and vertical > AP > ML, p ≤ 0.031) and foot-strike: ML(fore-foot and mid-foot strike > obvious heel strike, p ≤ 0.032), AP(fore-foot and mid-foot strikes > subtle-heel and obvious heel strikes, p ≤ 0.023). In each direction, the first loading rate peak occurred later during heel strike running relative to fore-foot(p ≤ 0.019), with vertical and 3 D resultant impact durations exceeding shear(ML and AP, p ≤ 0.007) in each condition.Conclusion: Loading rate–time assessment identified contrasting impact characteristics in each direction and the 3 D resultant following foot-strike manipulations, with potential implications for lower extremity structures in running.