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The countermovement jump, the V-cut test, the muscle thickness and the adjacent subcutaneous fat thickness of the gastrocnemius medialis and rectus femoris are important physiological indicators for success in basketball. The aims of this study were to evaluate between-age-category and between-gender differences in these indicators and examine the relationships between physical tests and ultrasound measurements. The measurements were recorded in a sample of 131 elite basketball players (66 males) who played in three age-categories (U14, U16, or U18). We performed two-way analysis of covariance tests and age-adjusted partial correlation analyses. U16 and U18 males showed better performance in the countermovement jump and V-cut tests and lower adjacent subcutaneous fat thickness of the gastrocnemius medialis and rectus femoris compared to the U14 males (p≤.001) and to age-category equivalent female players (p≤.001). Comparisons between the age categories in females did not show significant differences in any of the study variables. Adjacent subcutaneous fat thickness of the gastrocnemius medialis explained 22.3% of the variation for the countermovement jump result and 12.9% of the variation for the V-cut result in males (p<.01). This study is the first to show the association and predictive role of subcutaneous fat thickness measured by ultrasound in physical performance of male and female elite youth basketball players.

This study aimed to verify whether a group of young well-trained basketball players presented deficiencies in vitamin D concentration, and to analyze whether there was an association between vitamin D concentration and jumping and hopping performance. Gender differences were considered. Twenty-seven players from an international high-level basketball club (14 female, 16.00 ± 0.55 years; 13 male, 15.54 ± 0.52 years) participated in this cross-sectional study. Rate of force development was evaluated by means of the Abalakov test (bilateral: AbB; right leg: AbR; left leg: AbL); and the triple hop test (right leg: THR; left leg: THL). Blood samples were collected for the determination of serum 25-hydroxyvitamin D and nutritional status. Vitamin D insufficiency was found in both women (29.14 ± 6.08 ng/mL) and men (28.92 ± 6.40 ng/mL), with no gender differences regarding nutritional scores. Jumping and hopping performance was confirmed to be significantly larger in males (AbL, THR, and THL p < 0.005), whose CV% were always smaller. A positive correlation was found between AbB and vitamin D (r = 0.703) in males, whereas this correlation was negative (−0.611) for females, who also presented a negative correlation (r = −0.666) between THR and vitamin D. A prevalence of hypovitaminosis D was confirmed in young elite athletes training indoors. Nutritional (i.e., calciferol) controls should be conducted throughout the season. Furthermore, whilst performance seems to be affected by low levels of this vitamin in men, these deficiencies appear to have a different association with jumping and hopping in women, pointing to different performance mechanisms. Further studies accounting for differences in training and other factors might delve into these gender differences.

The countermovement jump (CMJ), the V-cut test, the muscle thickness (MT) and the adjacent subcutaneous fat thickness (SFT) of the gastrocnemius medialis (GM) and rectus femoris (RF) are important physiological indicators for success in basketball. The aims of this study were to obtain normative data regarding CMJ and V-cutperformance and ultrasound measurements, evaluate between-age-category and between-gender differences in these data and examine the relationships between physical tests and ultrasound measurements. The measurements were recorded in a sample of 131 elite basketball players (66 males) who played in three age-categories (U14, U16, or U18).We performed two-way analysis of covariance tests and age-adjusted partial correlation analyses. U16 and U18 males showed better performance in the CMJ and V-cut tests and lower GM and RF SFT compared to the U14 males (p ≤ .001) and to age-category equivalent female players (p ≤ .001). Comparisons between the females did not show significant differences in any of the study variables. V-cut and GMSFT variables explained 53.3% of the variation for the CMJ result in males (p < .01). This study reports normative data from CMJ and V-cut tests and ultrasound measurements of different age-category male and female elite youth basketball players. Furthermore, it is the first to show the association and predictive role of subcutaneous fat thickness in physical performance.