# Body Composition and Physical Performance by Playing Position in Amateur Female Soccer Players
## 4 Discussion  
This study analyzed differences in body composition and physical performance according to playing position in amateur female soccer players. Among the main results, midfielders were reported to have a significantly higher fat-free mass than goalkeepers, defenders, and forwards and a significantly lower body fat percentage than goalkeepers and defenders. Regarding physical performance, midfielders had a significantly higher jump height in DJ compared to the other positions, and goalkeepers showed a significantly lower ball-kicking speed for the dominant foot compared to the other playing positions. Meanwhile, midfielders only presented significantly higher ball-kicking speeds than goalkeepers in the non-dominant foot. However, no significant differences were reported in CMJ, SJ, and the 10 m, 20 m, and 30 m running sprint speeds by playing positions in amateur female soccer players. Our findings showed that midfielders had a higher fat-free mass than goalkeepers, defenders, and forwards. However, in the study conducted by [PERSON] et al. [18] on elite female soccer players, it was observed that forwards exhibited a significantly higher fat-free mass compared to midfielders (\(p\) = 0.04); this was similar to results reported by [PERSON] et al. [19] in a meta-analysis conducted on male soccer players showing that goalkeepers had a significantly higher fat-free mass with respect to defenders, midfielders, and forwards (\(p\) = 0.009). On the contrary, [PERSON] [20] reported no significant differences in first-division female soccer players in fat-free mass. The discrepancies in the studies may be because, physiologically, the demands of soccer vary according to the level of performance of the players, the style of play adopted by the teams, and the playing position [21; 22; 23]. For example, goalkeepers cover approximately 50% less total distance and <10% less distance at a high-intensity speed (>19.8 km/h) than field players [21; 24; 25], including also very brief explosive movements in matches. The lower energy expenditure during matches and training may influence their body composition, specifically the lower fat-free mass. In addition, midfielders cover a greater total distance (km) and perform more high-intensity running actions than defenders, while wide midfielders run greater distances than those in the line of defense, which could explain our findings [21]. Another result of the present study was that goalkeepers and defenders had higher body fat percentages than midfielders. These results are similar to those reported by [PERSON] [20], who reported that goalkeepers have a significantly higher body fat percentage than defenders (\(p\) = 0.03) in first-division female soccer players. However, they found no significant differences between elite female soccer players [18] and professional males [19] in body fat percentage by playing position. Similar to fat-free mass, our findings of higher body fat percentages in goalkeepers and defenders compared to midfielders can be explained by the physical demands of each playing position [21]. During training sessions, the weekly training load accumulated by field players is greater than that of goalkeepers, which influences their energy expenditure and, consequently, their body fat percentage [26]. An excess in body fat percentage, on the other hand, may present an advantage in the melee actions often experienced by defenders [21], who often have to retain the ball and protect it while dueling against the opponent seeking to get the ball. In contrast, midfielders were the leanest players, which favored their dynamically demanding role on the field [21]. Regarding the physical performance according to playing position, there were no significant differences in the vertical jump height for the CMJ test. These results are similar to those found in male professional soccer players [27] and fourth-division players [28]. However, the [PERSON] et al.