Efectos de un programa de entrenamiento pliométrico de 8 semanas sobre la potencia y fuerza muscular isométrica de miembros inferiores en futbolistas de categorías base

Abstract

Plyometrics is a training method based on utilizing the muscle stretch-shortening cycle, widely used for developing explosive strength and power in sports. The objective of this study was to determine the effect of an eight-week plyometric training program on power and isometric muscle strength of the lower limbs in youth soccer players from the Óscar Vesga Club in Bucaramanga. Methodology: A quantitative, experimental study was conducted with 25 male soccer players from the U-12 and U-13 categories of the Óscar Vesga Club in Bucaramanga. The sample was selected by convenience sampling and subsequently randomized and assigned to an experimental group (n = 13) and a control group (n = 12). Both groups were evaluated before and after the intervention using vertical jump tests (countermovement jump and squat jump) for power, and isometric strength tests of the quadriceps and hamstrings. The plyometric training program focused on developing explosive lower limb strength over 8 weeks (L: 8 Weeks, D: 30-45 minutes per session, F: 2/7, I: 60-75% of HRmax, V: 1/2/8/10 minutes, M: III, and Den: 1:1). Data analysis included descriptive statistics and Student's t-tests for intragroup and intergroup comparisons, with a significance level of p < 0.05. Results: In the experimental group, a significant increase was observed in CMJ power (W) (559.98 ± 93.80 vs. 576.65 ± 79.14; p = 0.017) and in right quadriceps isometric strength (4566.10 ± 962.91 N vs. 4989.94 ± 1062.32 N; p = 0.003). The other jump variables (SJ and CMJ height) and isometric strength did not show statistically significant changes (p > 0.05). In the control group, no improvements were observed in the jump tests (p > 0.05) and a significant decrease was recorded in the strength of the left quadriceps (4775.26 ± 1157.24 vs. 4315.20 ± 1060.07; p = 0.010) and right quadriceps (4971.20 ± 1485.56 vs. 4326.55 ± 1083.41; p = 0.013). Conclusions: 8 weeks of plyometric training generate positive effects on power and isometric muscle strength of lower limbs in youth soccer players.