Influencia de la densidad de jugadores sobre la frecuencia cardíaca y respuestas técnicas en jóvenes jugadores de fútbol Influence of the density of players on their heart rate and its technical implica- tions on young football players

The purpose of this research was to find out the impact of the physiological and technical aspects of three different situations of small-sided games (SSG) on young football players. The different situations considered were 3 vs 3, 4 vs 4 and 5 vs 5 in a space of 30x30 m, implemented by 10 young male football players (age 9.3 ± 0.7; height 138.5 ± 10.5 cm, weight 41.9 ± 6 kg and 2.2 ± 1.4 years' experience). The technical actions were quantified out of video recordings and the physiological performance of the exercise was measured through the heart rate (%HRmed and %HRpico), and the rated of perceived exertion (RPE). The results of variance analysis (ANOVA) show significant differences in the following variables: good passes, bad passes, average HR, maximum HR; time 70-79% and between > 90%HRmax and PSE. The results point out that the manipulation of the density of the tasks has effects on different levels and must therefore be taken into account by the coaches that work with young players when it comes to designing training tasks. The main conclusion is that the use of the 3 vs 3 format seems more demanding both for technical purposes and aerobic performance. A b s t r a c t