Background: Body composition strongly influences the performance of flag football (FF) players, which makes anthropometric measurements important. With the growing popularity of FF, understanding body composition requirements for both male and female players is essential to help optimize their performance. Purpose: This study aimed to characterize and compare anthropometric and body composition profiles between male and female FF players across different playing positions. The study was conducted during the European Flag Football Championship organized by the International Federation of American Football (IFAF).Methods: A cross-sectional study design was used. Anthropometric measurements followed the International Society for the Advancement of Kinanthropometry (ISAK) full profile protocol. Data were collected from 91 male and 48 female players, and body composition was estimated using the five-way fractionation method. Comparisons between males and females were performed using analysis of variance (ANOVA), with statistical significance set at p < 0.05.Results: Normative reference values and percentiles for anthropometric variables and body composition were established for male and female FF athletes. Male players had an average sum of eight skinfolds of 83.5 ± 30.5 mm, muscle mass of 36.0 ± 7.4 kg, and adipose mass of 19.8 ± 5.1 kg. Female players (27.4 ± 4.5 years) had an average sum of 8 skinfolds of 115.5 ± 40.9 mm, muscle mass of 27.8 ± 4.0 kg, and adipose mass of 20.5 ± 4.8 kg. Both sexes predominantly presented a mesomorphic somatotype.Conclusion: This study provides valuable data on anthropometric characteristics of male and female FF players. These results can help create normative reference values and support strategies for performance optimization. Additionally, findings contribute to better understanding of body composition needs in FF athletes of both sexes.

Background: This cross-sectional observational study aimed to describe the position-specific kinanthropometric characteristics of Mexican professional American football players competing in the 2019–2020 seasons of the Liga de Fútbol Americano. Methods: A total of 189 athletes were assessed following International Society for the Advancement of Kinanthropometry standards. Twenty-six anthropometric variables were measured to estimate body composition (five-way fractionation), somatotype, proportionality indices, and tissue-specific masses. Positional differences were examined using ANOVA or Kruskal–Wallis tests with corresponding effect sizes (η² or ε²). An exploratory stepwise discriminant analysis identified the anthropometric dimensions contributing most to positional differentiation, and classification accuracy was calculated. Results: Offensive and defensive linemen showed the greatest absolute size and higher adipose, muscle, and bone mass compared with other positions. The overall somatotype corresponded to a balanced endomorphic mesomorph (3.8–7.0–0.8), with wide receivers and defensive backs presenting lower endomorphy. The discriminant model identified arm relaxed girth, biiliocristal breadth, and sitting height as the variables contributing most to positional differentiation, achieving a classification accuracy of 57.7%. Given its exploratory nature and the absence of cross-validation, the discriminatory capacity of the model should be interpreted with caution. Somatotype Attitudinal Mean indicated greater interpositional heterogeneity among linemen. Conclusions: This study provides population-specific reference data for Mexican professional American football players, highlighting clear positional morphological characteristics. These findings may support talent identification and positional profiling; however, the exploratory discriminant model and league-specific sample limit generalization to other populations.

Although Flag Football (FF) is growing worldwide, the literature to guide sports sciences in preventing injuries is scarce. The aim of this study was to analyse how anthropometric characteristics were associated with injury in elite FF players. Athletes completed a full profile according to the International Society of Advances in Kinanthropometry (ISAK), including weight, height, sitting height, arm span length, skinfolds, girths, length and breadth bones, and an injury questionnaire was administered. Logistic regression models and Receiver Operating Characteristic (ROC) curves were conducted. In total, 108 FF national team players, 34 female (26.7 ± 4.3 years old) and 74 male (26.9 ± 5.1 years old), participated. Of these, 62% FF players reported injuries. Relaxed arm and flexed and contracted arm girths are related to increased or reduced injury risks (Odds = 2.932, p = 0.008; Odds = 0.335, p = 0.009, respectively), while longer tibia length and higher muscle mass also increase the risk (Odds = 1.407, p = 0.034; Odds = 1.223, p = 0.010, respectively). Specific cut-off points were defined by sex, such as hip circumference, established at 103 cm in the Anterior Cruciate Ligament (ACL) model for males, increasing the risk by 5 times. Anthropometric characteristics were related to injury incidence and could be used by sports science practitioners as an efficient decision-making tool to describe and analyse the static and dynamic components of FF players in injury prevention.