Nutritional Habits, Body Composition, and Sports Performance in Adolescent Swimmers—A Cross-Sectional Study

Background. A substantial body of scientific evidence indicates a close association between dietary habits, body composition, and athletic performance. Nevertheless, dietary inadequacies remain prevalent among athletes, including adolescents. The present study aimed to assess the body composition and dietary habits of participants in the Junior National Swimming Championships. Methods. The study included 39 female competitors (17.8 ± 0.2 years) and 88 male competitors (17.7 ± 0.4 years), all of whom provided informed consent to participate. Dietary habits were evaluated using a questionnaire developed in accordance with the principles of the Swiss Food Pyramid. Additionally, participants provided information regarding their training workload, including the number of weekly training sessions and the total distance swum during training. Body composition was assessed using bioelectrical impedance analysis (Tanita BC-418 MA). Results. Male swimmers exhibited significantly different values across all body composition variables compared with female swimmers (p < 0.05), whereas no significant differences were observed in training workload between the groups. Regardless of sex, the majority of participants reported consuming at least three meals per day, as well as the recommended amounts of dairy products and fruit. In contrast, fish consumption was below the recommended level. Female swimmers consumed sweet snacks and fast food significantly less frequently than their male counterparts (p < 0.05), whereas male swimmers reported a higher frequency of pork product and sugar-sweetened carbonated beverage consumption (p < 0.05). Conclusions. Young competitive swimmers exhibit several nutritional inadequacies. Although their consumption of fruit and vegetables generally aligns with current dietary recommendations, fish intake remains insufficient. Female swimmers demonstrated more favourable dietary patterns than male swimmers. Accordingly, ongoing nutrition education should constitute an integral component of the athletic training process.