Somatic and Psychological Profile of Athletes Across Seasonal Cycles

This observational longitudinal study will examine the somatic and psychological profile of team sport athletes across seasonal training cycles. The study will include male and female athletes who play football, volleyball, or ice hockey. The planned study population consists of 300 participants, including 200 adults aged 18 to 38 years and an additional 100 adolescent athletes aged 14 to 17 years. Participants will be assessed at two time points, before and after a transitional period in the annual training cycle, such as the off-season, holiday break, preparatory period, or competitive period. These periods are associated with changes in training load, recovery, daily routine, and lifestyle, and may therefore influence both body composition and psychological functioning. The longitudinal design will allow evaluation of changes over time and identification of factors associated with more favorable or less favorable adaptations. The study will assess body composition and selected behavioral and psychological characteristics. Adult participants will undergo body composition assessment using bioelectrical impedance analysis and dual-energy X-ray absorptiometry (DEXA). Adolescent participants included under the approved amendment will undergo the same study procedures except for DEXA. All participants will complete standardized self-report questionnaires assessing eating behavior, physical activity, sport-related perfectionism, and body esteem. The questionnaires used in the study include the Three-Factor Eating Questionnaire (TFEQ-13), the International Physical Activity Questionnaire (IPAQ), the sport perfectionism questionnaire, and the Body Esteem Scale. These tools will be used to examine whether eating behaviors, activity patterns outside formal training, perfectionism, and body image are associated with changes in body composition and related characteristics across different phases of the sports season. The main goal of the study is to improve understanding of how seasonal changes in training and daily habits affect the physical and psychological characteristics of athletes. The results may help identify factors linked to beneficial or unfavorable changes in body composition and well-being, and may support the development of more individualized monitoring, nutrition, training, and psychological support strategies for athletes. Participation in the study is voluntary. All participants, and legal guardians in the case of minors, will receive information about the study procedures, potential risks, and study aims before consent is obtained. Data will be handled confidentially and analyzed in anonymized form. Study findings are intended for scientific publication and for practical application in athlete monitoring and care.