Leg strength and stiffness as ability factors in 100 m sprint running

摘要

Background. The purpose of this study was to determine the importance of leg strength and stiffness relative to ⅰ) 100 m sprint performance, ⅱ) mean speed on the three phases of the 100 m race (30-60-100 m) and ⅲ) the speed differences between these phases. Methods. Nineteen regional to national level male sprinters competed in a 100 m race. Video analysis was used to determine mean velocity parameters. Two subgroups were created since some of the runners decreased their velocity during the third phase (G_1), whereas others maintained or accelerated it (G_2). Leg strength (concentric half-squats - counter movement jump) and stiffness (hopping) were determined. Simple (r) and multiple regressions (R) were used. Results. The mean performance over 100 m was 11.43 sec (10.72-12.87 sec). The concentric half-squats were related to 100 m (r=0.74, p<0.001) and to the mean speed of each phase (R=0.75, p<0.01). The counter movement jump was related to 100 m (r=0.57, p<0.05) and was the predictor of the first phase (r=0.66, p<0.01). The hopping test was the predictor of the two last phases (R=0.66, p<0.05). Athletes who had the greatest leg stiffness (G_1) produced the highest acceleration between the first and the second phases, and presented a deceleration between the second and the third ones. Conclusions. The concentric half-squats test was the best predictor in the 100 m sprint. Leg stiffness plays a major role in the second phase.