Effects of different training methods on female soccer players' lower extremity strength and performance

The aim of this study was to compare the effects of small-sided games (SSGs) and running-based high-intensity interval training (HIIT) on performance, lower extremity strength and body composition of female soccer players. This study followed a randomized parallel study design. Twenty-four female soccer players (age: 18,63 ± 2,36 years) were randomly allocated to two training groups (SSG, n = 12; and HIIT, n = 12). The training intervention had a duration of eight weeks, consisting of three training sessions per week. Players were assessed twice (pre- and post-intervention) for anthropometrics (height, body mass and skinfold measurements), vertical jumping (CMJ and DJ), horizontal jumping (5 different hop tests), sprinting (10- and 30-m), change of direction and final velocity at 30-15 Intermittent Fitness Test (30-15 IFT). A covariance analysis (ANCOVA) was used to determine differences between groups in the post-intervention by controlling for covariates (pre-intervention). The within-group analysis was performed using a paired t-test, while the between group analysis per assessment moment was performed using and independent t-test. The between-group analysis with ANCOVA revealed that there are no significant differences between the SSG and HIIT groups in the post-intervention for any outcome (p>0,05) except for change-of-direction (p<0,05). The within-group analysis revealed significant improvements in both the SSG and HIIT groups in vertical and horizontal jumping (p<0,05), reactif strength index (RSI) (p<0,05), aerobic performance (p<0,05) and change of direction (COD) (p<0,05). For the anthropometrics, while significant changes found for body mass and index in SSG, significant changes found for abdominal skinfold in HIIT (p<0,05). When we evaluate the results of the study, it is revealed that SSG and HIIT are both effective training methods for improvig vertical and horizontal jumping ability, change-of-direction, and aerobic capacity status measured at a progressive and intermittent multistage test in soccer players.