Twenty four male Sport Science students, were assigned in this study in order to be examined the acute effects of different loading conditions on acceleration, maximum speed and final performance of a 50 m sprint run. A countermovement jump and a 50 m run without and with extra loading - 8, 15, 20% of subjects' BM were performed in order leg power and running performance to be measured. ANOVA revealed significant interaction between loading conditions and performance (Wilks ËF = 31.34, p = 0.000, n2 = 0.967). The 8% B.M. loading significantly affected performance at 40 m by 4.6 - 4.7% while the 15% BM loading at 20 and 40 m by 7.3 and 7.4% respectively. The 20% BM loading affected similarly running performance at 10 m and 40 m causing an increase in performance by 9.9% at both distances. Significant correlations were found between leg power and running performance for the selected distances at the loading conditions of 0, 8, 15% BM (r = - 0.440 - 0.553), while a correlation between leg power and running performance with the load of 20%B.M. was found only for the distances 30, 40 and 50 m (r = - 0.419 - 0.565). Subjects with higher leg power were more affected by large loads (15-20% BM) during the acceleration phase, while in those with lower leg power decreases occurred by all loading conditions. Consequently, resistance speed training using a weighted vest emerges an excellent means for either phase of the 0 - 50 meters.
© Copyright 2014 Biology of Exercise. University of Peloponnese. All rights reserved.