| Abstrakt: |
Introduction: The purpose of this study was to investigate the effects of a 4-week barefoot sprint training program on sprint biomechanics and stretch-shortening cycle jump ability. Methods: Fourteen children with no experience in barefoot sprinting were randomly assigned to 1 of 2 groups: a barefoot training group (3 boys and 4 girls; age, 11.0 ± 0.8 years-old; height, 143.1 ± 8.4 cm; body mass, 35.4 ± 5.6 kg; shoe mass, 0.17 ± 0.02 kg) and a control group (3 boys and 4 girls; age, 11.0 ± 0.8 years-old; height, 142.6 ± 8.2 cm; body mass, 34.4 ± 6.4 kg; shoe mass, 0.18 ± 0.01 kg). The 4-week intervention consisted 40 minutes of sprint training per weekly session using the allocated footwear. Before and after the intervention, 2-dimensional biomechanical analysis of the 50-m maximal sprint under both shod and barefoot conditions, and the countermovement jump and 5 repeated rebound jumping tests were performed by both groups. Pre- to post-test changes in spatio-temporal parameters and sprint kinematics, and jump heights for both jump types, and the contact time and rebound jump index for the rebound jump, were analysed using 2-way mixed ANOVA. Results and Discussion: After the 4-week intervention, a higher step frequency (p <0.01), a longer step length (p <0.05), and a higher sprint velocity (p <0.01) were observed in the barefoot training group, although no change was observed in the foot strike patterns and the swing leg velocity. The barefoot training group showed a higher rebound jump index (p <0.05) and a shorter contact time (p <0.01), while no differences were evident in the counter-movement jump height. These results suggest that 4-week barefoot sprint training seems to be an effective strategy for improving certain aspects of sprint biomechanics and for development of fast stretch-shortening cycle ability in children. [ABSTRACT FROM AUTHOR] |
