## 4 Discussion
study, but with the same body classification [50], just as in another study carried out with 86 Spanish players with similar values and the same classification (3.82-3.27-2.01) [48]. These body composition variables could be related to a greater or lesser extent with some skills necessary for sports practice, such as agility, aerobic capacity, lower body power, and speed. In relation to agility, the time obtained in the \(t\)-test measurement was higher than those obtained in other studies with athletes trained in other sports with similar characteristics [40]. In contrast, the scientific literature has described a direct relationship between the assessment of aerobic capacity in a level 1 intermittent endurance Yo-Yo test, and the physical performance in an indoor football match, of high-level competitive players [51]. The mean VO\({}_{2}\)max values obtained in this study were within the mean values found in studies related to intermittent sports [51; 52; 53] and there was no clear evidence that higher VO\({}_{2}\)max values significantly improved competitive performance in this discipline [53]. Another of the determining variables of performance in indoor football is the explosive power of lower extremities [22]. In the study carried out by [PERSON] et al. (2009) [54], it was observed that indoor football players obtained lower values in the vertical jump (38.1 cm) than outdoor football players (44.9 cm), which may be due to the fact that in indoor football, there are fewer frequent actions in which vertical jumps are performed or needed, as the ball travels for a longer period at ground level. The results of our study (31.47 cm) and another study carried out with elite female futsal players (26.7 cm) [9] showed lower values than those obtained in the male sex due to the greater muscle power developed in the male sex. As for the CMJ and SJ vertical jumps, no correlations were found with the anthropometric variables. On the other hand, the flight time and height of the ABK jump correlated with the height of the female players. The highest correlations obtained in our study are shown between mesomorphy and the time employed running 25 m, both in the overall mean (r = 0.612) and the mean of the best times (r = 0.624). To measure speed in futsal, some studies have used different distances [38; 55], and 25 m may be a slightly excessive distance in futsal [56]. After analyzing the results of our study, and in comparison with the literature found, we can say that a percentage of muscle mass, related to the mesomorphic component, could improve the speed factor, as documented in other studies related to acceleration and speed and muscle mass [57; 58; 59], with this being an advantage for indoor football players when performing technical and motor actions during a match [9]. From the results of our study, a mean inverse correlation between fat percentage and total VO\({}_{2}\)max derived from the Yo-Yo test was found (r = -0.590; \(p\) = 0.094); this was also corroborated by the data obtained from the skinfolds, which also showed a significant inverse correlation for the parameters of abdominal skinfold with VO\({}_{2}\)max (r = -0.772; \(p\) = 0.015) and abdominal perimeter with VO\({}_{2}\)max (r = -0.685; \(p\) = 0.042). Furthermore, a correlation was also observed between muscle mass values and aerobic capacity (r = 0.513; \(p\) = 0.158), which may indicate that levels of muscle mass close to 40%, and low levels of fat mass, could contribute to the development of good aerobic capacity. Our study showed a strong correlation between agility and anthropometric variables related to the fatty compartment (sum skinfold, abdominal skinfold, biceps skinfold, and endomorphic component), indicating that the lower the value measured in these variables, the greater the agility that can be developed for the performance of actions typical of indoor football such as changes in direction, accelerations, or decelerations, but no references have been found in the scientific literature that relate agility to these variables.