The goal of this observational study is to determine if physical activity and the adherence to a Mediterranean diet have a relationship with body composition, growth, and maturation status in youth triathletes. The main question it aims to answer is:

• Is body composition (fat and muscle) determined primarily by growth and biological maturation or by physical activity and the Mediterranean diet in youth triathletes? Participants already have been evaluated in body composition, mediterranean diet adherence and practical of physical activity during 3 years.

Triathlon is an individual, multidisciplinary and resistance sport with three stages: swimming, cycling and running, linked by two transitions. The importance of knowing body composition, eating patterns, level of physical activity and maturational state, will allow influence on training, increasing sports performance.

Regarding body composition and its relationship with performance, it has been observed that the greater the body fat, the lower the physical performance of triathletes. In each sport, athletes have different composition somatotypes. For triathlon, it is difficult to establish a specific somatotype, since it is a modality that encompasses three sports, among which the anthropometric characteristics of the athletes who practice them are not similar. In addition, since it is a relatively new category, there are not enough bibliographical references regarding anthropometry and body composition.

During biological maturation, there is an increase in the basal metabolic rate, so an optimal diet helps the growth process and improves the performance and recovery of athletes. Therefore, in the early stages of childhood and adolescence, adherence to the diet plays an important role in the acquisition of healthy lifestyles to determine an optimal state of health. The Mediterranean Diet model is associated with healthy eating habits, high levels of quality of life and physical benefits.

Inclusion Criteria:

• Acceptation of informed consent by parents

Exclusion Criteria:

• No attendance to body composition evaluation
• Reporting less than 80% of assistance to physical activity sessions reported by trainer

Young triathletes belonging to the ADESAVI triathlon club from the city of San Vicente del Raspeig (Spain)

The data are available from the authors on request from the IP JMMS (josemiguel.ms@ua.es).