## 4 Discussion  
The purpose of this study was to examine and investigate changes in the cardiorespiratory performance of female soccer, basketball, and handball athletes during the annual training cycle. In addition, we aimed to compare the results between the measurements in the three different team sports before the start of preparation, in the middle, and at the end of the season. The results of the study showed that in all three sports, the maximum oxygen uptake increased in the middle of the season, while at the end of the season, it decreased to initial levels and handball even lower. In the anthropometric characteristics, the differences observed in the first measurement continued to appear in the other two measures between sports. The differences between the three measurements showed no significant differences. However, in all sports, there was a slight decrease in body mass, lean body mass, and body fat percentage. This decline was progressive between the three measurements. Body weight affects relative VO\({}_{\text{2 max}}\). An increase in relative VO\({}_{\text{2 max}}\) was observed in the study, but it cannot be attributed to a decrease in body mass, as in the third measurement, while there was an additional drop in body weight, there was no increase in relative VO\({}_{\text{2 max}}\). On the contrary, there was a decrease in initial levels. VO\({}_{\text{2 max}}\) (absolute and relative) was higher in soccer players from the start of the preparation until the end of the season compared to the other two team sports. As mentioned above, aerobic capacity plays an important role in the performance of female soccer players, perhaps greater than the other two sports. This leads coaches and athletes to place greater emphasis on this ability. Additionally, the field in which the female soccer athletes train is much larger compared to the fields of the other two sports. As a result, female soccer players cover longer distances during training sessions, resulting in higher maximum oxygen uptake. The evaluation of cardiorespiratory performance found that the relative VO\({}_{\text{2 max}}\) values of soccer athletes in this study were higher than those of Australian college athletes, Turkish athletes, and England international athletes [33], while they were similar to those of the Japanese national soccer team and England's high-level athletes [34]. The values were lower than those mentioned for Danish female athletes [34]. VO\({}_{\text{2 max}}\) (absolute and relative) of soccer athletes in this study showed changes between measurements, increasing significantly in the middle of the season and falling at the end of the season. The relative VO\({}_{\text{2 max}}\) of basketball athletes was similar to those reported in previous studies for high-level basketball athletes [5; 12] and showed an increase in the middle of the season with a fall that followed at the end of it. In handball athletes, as in the female athletes of the other two team sports, an increase in VO\({}_{\text{2 max}}\) was observed in the second measurement with a drop in the third measurement to starting levels. The relative VO\({}_{\text{2 max}}\) of athletes in this study was similar to those reported in previous studies on handball athletes [16] and lower than some previous studies [35]. The increase in relative VO\({}_{\text{2 max}}\) observed in the middle of the season and the drop at the end is also in line with the research of [PERSON] and [PERSON] (2009) [36], who observed a drop in fatigue of the soccer athletes in their study, as well as the burden of the second half of the season. The values of handball athletes were higher compared to basketball athletes and lower than soccer athletes, who showed the highest values in all three measurements during their annual training cycle compared to the other two team sports. In the exercise time until exhaustion, there was no difference between the three measurements in the soccer and handball athletes. Basketball athletes showed a difference between the three measurements.