Caracterização da corrida de 75 metros de atletas da categoria sub-16 do atletismo

Abstract

It is valuable for coaches to know the phases of the 75m dash race. This knowledge allows them to develop specific training protocols for young athlete's performance for this test. It is known that the age levels from 10 to 15 years old is considered a sensitive stage in the development of physical qualities, that is when they start to show faster improvements mainly due to maturational factors. Thus, this study aims to investigate the behaviour of the velocity curve in the athletes from 13 to 15 years realizing the test of 75 meter dash. It also aims to characterize the main influential variables in the performance of this race, and compare the fastest to the slower athletes. We evaluated 79 athletes from track and field, 34 boys and 45 girls, 10 teams in the Under-16 age levels. The protocol was developed on two consecutive days. On the first day, the clinical historic data was collected, including anthropometry data (weight, height, sitting height, wingspan and skin folds) and the movement velocity test and vertical jump. On the second day, athletes ran the 75m race. The main results were: acceleration phase goes from 0 to 30m for boys and girls, maintenance phase goes from 30 to 67.5m for boys and from 30 to 45 m for girls and decelerating ranges from 67.5 to 75 m for boys, and from 45 to 75m for girls. The boys' stride length is more decisive than their stride frequency. For girls, both variables had the same importance. The vertical jump is a good predictor of performance in the race of 75 m. Faster boys have better anthropometric and performance in relation to slower participants. Faster and slower boys accelerate to 30 m, though the slowest holds from 30 to 60 and decelerate from 60 to 75, while in contrast the fastest keep the speed of 30 m until the end of the race and do not slow down. Faster girls compared to slower pairs do not differ in anthropometric values, differentiating the sum of skinfolds and the performance variables such as strength. The duration of the phases of faster and slower girls are alike. The only difference is the best values of speed of the fastest participants. It can be concluded that young athletes of the U-16 levels have the same duration of acceleration phase regardless of sex or performance level. What differs is the speed during the maintenance phases and deceleration. The force is a prominent variable to predict the speed performance in this category.