The purpose of this study was to examine the effects of speed training on sprint step kinematics and performance in male sprinters. Two groups of seven elite (best 100-m time: 10.37 ± 0.04 s) and seven sub-elite (best 100-m time: 10.71 ± 0.15 s) sprinters were recruited. Sprint performance was assessed in the 20 m (flying start), 40 m (standing start), and 60 m (starting block start). Step kinematics were extracted from the first nine running steps of the 20-m sprint using the Opto-Jump-Microgate system. Explosive power was quantified by performing the CMJ, standing long jump, standing triple jump, and standing five jumps. Significant post-test improvements (p < 0.05) were observed in both groups of sprinters. Performance improved by 0.11 s (elite) and 0.06 s (sub-elite) in the 20-m flying start and by 0.06 s (elite) and 0.08 s (sub-elite) in the 60-m start block start. Strong post-test correlations were observed between 60-m block start performance and standing five jumps (SFJ) in the elite group and between 20-m flying start and 40-m standing start performance and standing long jump (SLJ) and standing triple jump (STJ) in the sub-elite group. Speed training (ST) shows potential in the reduction of step variability and as an effective short-term intervention program in the improvement of sprint performance.
Keywords: kinematics; speed; sprint exercises; sprinting; step variability.