## 2 Materials and Methods
### Anthropometric and Body Composition Assessment  
All anthropometric and body composition indices were assessed, including body mass (kg), body height (cm), body mass index (BMI), body fat percentage (BF%), fat mass (FM), fat-free mass (FFM), and the sum of 8 skinfolds (mm). The body fat percentage (%) was  
\begin{table}
\begin{tabular}{l l  
calculated using the Carter equation for men: [BF% 0 2.585 + 0.1051 \(\times\)\(\sum\) X], where X represents the sum of the tricipital, bicipital, subscapular, iliac-crest, thigh, and calf skinfold thicknesses [21]. The selection of the Carter equation for calculating body fat percentage is based on its empirical validation and comparative effectiveness over other models. The Carter equation, primarily reliant on skinfold measurements, has been shown to provide a reliable estimate of body fat percentage, particularly across diverse populations. This adaptability is crucial, as body composition assessment tools must be relevant to various demographic groups to ensure accuracy. One key advantage of the Carter equation is its strong correlation with more advanced body composition assessment methods, such as dual-energy X-ray absorptiometry (DXA). Studies have demonstrated that skinfold thickness measurements, integral to the Carter equation, offer better predictive accuracy for body fat percentage compared to simpler anthropometric variables like body mass index (BMI) [22]. This is particularly significant because BMI often fails to differentiate between fat mass and lean mass, potentially leading to misclassification of an individual's body fat status [23]. Furthermore, the Carter equation has been validated across various ethnic groups, enhancing its applicability. Research indicates that the equation performs well in different populations, including adolescents and adults, making it a versatile tool for clinicians and researchers [24]. Accurate estimation of body fat percentage is critical, as it is associated with numerous health outcomes, including obesity-related diseases [25]. Another significant factor favoring the Carter equation is its practicality. The method requires minimal equipment--primarily skinfold calipers--making it accessible for use in both clinical settings and fieldwork. This contrasts with more complex methods, such as bioelectrical impedance analysis (BIA) or DXA, which may not be readily available in all contexts [26]. The simplicity and cost-effectiveness of the Carter equation make it an appealing option for widespread application in body composition assessment. Summing up, the rationale for choosing the Carter equation over other models lies in its empirical validation, adaptability across populations, and practical application. Its ability to provide a reliable estimate of body fat percentage while being both accessible and cost-effective positions it as a preferred choice for clinical and research use alike. The fat mass (FM) in kilograms was calculated by dividing the body fat percentage (BF%) by 100 and then multiplying it by the athlete's total body weight (kg). The fat-free mass (FFM) in kilograms (kg) was then calculated by subtracting the FM (kg) from the total body mass. During the anthropometric measurements, the participant wore only a swimsuit, with no shoes or objects on his hands or head. The anthropometric measurements were performed twice, in accordance with the guidelines of the International Society for the Advancement in Kinnthropometry (ISAK) by a level 1 certified anthropometrist, considering the corresponding intrapersonal technical error of measurement (TEM): 5% for skinfolds and 1% for other measurements [27]. It used the following formula for TEM and was calculated for each variable (Table 2):  
\[\text{TEM}=\text{SD}\times\text{\sqrt{CV}}\%/100\] \begin{table}
\begin{tabular}{c c} \hline \hline
**Variables** & **TEM** \\ \hline Weight (kg) & 0.24 \\ \hline Body fat (\%) & 0.15 \\ \hline Skinfolds (mm) & 2.20 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Technical error of measurement.