摘要：A 100 m race is essentially running from point A to point B as quickly as possible, thus, deviations from a straight linear path may cause performance detriments. This study elucidates the importance of running straight during linear sprinting. A new descriptive characteristic of sprint running (step straightness) was defined and measured, representing the mediolateral distance of step-to-step centre of pressure foot position relative to the centre of an athletic track lane. The mediolateral distance away from the middle of a running lane (step straightness) is an indicator of deviating from a straight linear sprint path.The purpose was to clarify whether step straightness is a determinantof performance, kinetic and kinematic sprint characteristics during the initial, middle, later and total acceleration phase sections. Eleven sprinters and thirteen baseball players performed 60 m maximal effort sprints over a long force platform system. Step-to-step ground reaction force was used to calculate step straightness, running speed, step length, step frequency, support time, flight time, step width, mediolateral positive impulse, mediolateral negative impulse, mediolateral net impulse, propulsive impulse, braking impulse, anteroposterior net impulse and effective vertical impulse. Pearson correlations demonstrated nostatistically significant (P > .050; trivial–moderate effects) associations between step straightness and any performance, kinetic or kinematic variables measured, suggesting that step straightness is not a performance determinant. It was concluded that there may be no practical importance of straightness during linear sprinting.The practical implication of this study was clarifying that there may be no need for coaches to encourage the straightness of running during linear sprinting or for athletes to concentrate on their body position in a lane relative to straightness.
关键词：Step width;Centre of pressure;Over-line sprinting;Linear sprinting;Ground reaction force;Spatio-temporal
