Influence of anthropometric and fitness variables on the probability of being selected for competing in the national championship in adolescent volleyball players

Objective: The objective of the present research was to analyse the influence of anthropometric variables, physical condition, chronological and biological age, and training variables on the possibility of being selected for the regional team competing in the national championship in adolescent volleyball players.

Methods: A total of 100 volleyball players (48 boys, age 14.17 ± 1.00 years; 52 girls, age 14.22 ± 1.14 years) participated in the present cross-sectional design study and completed a sociodemographic and sports questionnaire. Participants underwent an anthropometric assessment, including basic measurements, skinfolds (triceps, subscapular, biceps, iliac crest, supraspinal, abdominal, thigh and calf), girths (arm relaxed, flexed and tensed arm, waist, hips, middle thigh and calf), breadths (biacromial, biiliocristal, humerus, femur, and bi-styloid), lengths (acromiale-radiale, radiale-stylion and stylion-medio-dactylion); and a height (iliospinale). After that, ∑6 and ∑8 skinfolds, body composition, upper limb length and corrected girths were calculated. Physical fitness was assessed by sit-and-reach, back scratch, long jump, medicine ball throw, countermovement jump, sprint and agility test. The maturity offset was estimated. Statistical analysis included χ2, to analyse differences between those selected and not selected, and odd ratio (OR), to assess the possibility of being selected for competing in the national championship as a function of anthropometric, physical fitness and training variables.

Results: It was observed that, in the group of boys, higher values in the variables related to bone mass increased the possibility of being selected (OR = 2.17-3.08). Better performance in the physical tests related to power production was a predictor of higher chances of being selected in both groups of boys and girls (OR = 0.48-2.53). In the case of the boys, a more advanced maturation process increased the possibility of being selected (OR = 0.61-1.69). Better perception of the coach in both groups and higher training volume in the case of the boys increased the chances of being selected (OR = 1.75-3.70).

Conclusions: Better performance in the physical condition tests is an indicator of a greater probability of being selected in both boys and girls, while the anthropometric variables, a higher biological age, the volume of training and perception of the coach were the only determinants in the group of boys.