Abstract
The main goal of this study was to determine whether the type of spike can influence the final sprint result by comparing step by step the kinematics of four 50-m sprints. Twelve well-trained junior sprinters (ages 17-19) from the Polish National Team (ranging from 100 to 400 m) participated in the study, with personal bests in the 100-m sprint of 10.70 ± 0.19 s. The OptoJump Next-Microgate sensor measurement system (Optojump, Bolzano, Italy) was used to measure the essential kinematic sprinting variables. Following the sprint distance, photocells were placed on the track at the start, at 10 m, at 20 m, at 30 m, and at the finish (50 m). Fifty-meter sprints were completed alternately, two with classic and two with the carbon-plated spikes. For every sprinter, the order in which the spikes were chosen was randomized. To better understand the problem of variability in kinematic parameters, in addition to the actual statistics, the profile analysis process was applied. The analysis of the four 50 m sprints did not show significant differences between the kinematic parameters considering runs in both the classic Nike and carbon-plated Nike ZoomX Flymax spikes. It may be suggested that spikes' sole bending stiffness may not affect short-distance (up to 50-60 m) sprinting performance. From a practical point of view, training focused on maximum speed development can be carried out with both classic and carbon-plated spikes. Finally, our experiment can guide the preparation of a research methodology that assesses the effect of carbon-plated spikes on prolonged sprinting, e.g., 200-400 m.