Relação da idade óssea com antropometria e aptidão física em jovens praticantes de voleibol

Reliability of biological maturation analyses performed by equations predicting skeletal age and peak height velocity with hand and wrist X-ray results

BACKGROUND

Hand-wrist radiography is the gold standard for the assessment of skeletal age (SA) and the assignment of biological maturation (BM) status. However, its practical use in the field is questioned, prompting the development of anthropometric equations to estimate BM. However, there is no consensus on the reliability of these equations in relation to hand-wrist X-rays.

OBJECTIVE

To test the reliability of the BM estimated from predictive equations with the results of hand-wrist X-rays.

METHODS

One-hundred forty-four young athletes (38%-males, 62%-females; 12.3 ± 1.4 years) were recruited. SA was assessed by analyzing X-rays of the hand-wrist using the Greulich-Pyle protocol. SA was predicted using the anthropometric equations of Cabral and Macêdo. By subtracting chronological age from SA, a measure of BM or biological age (BA) was computed. In addition, a BA of years from peak height velocity (PHV) was predicted using the anthropometric equations of Mirwald and Moore.

RESULTS

Relative to X-ray, Cabral's equations showed high reliability in estimating BM in both sexes (p < .0001) while Macêdo's equations showed substantial reliability or males (p < .0001) only. Mirwald and Moore's equations showed weak reliability (p < .05 and p = .043, respectively).

CONCLUSION

The prediction of SA using anthropometric equations was found to be reliable in categorizing individuals as late, synchronized, and/or early maturers in both sexes. However, the predictive equations of years from PHV only reliably categorized late and synchronized maturation stages in males and the synchronized maturers in females.

Biological Maturation and Hormonal Markers, Relationship to Neuromotor Performance in Female Children

Background: Mechanisms that influence muscle strength can interfere with neuromotor performance and overall health, thus hormone markers and maturation can interact in this process. Objective: The present study aimed to verify the relationship of hormonal markers and biological maturation on neuromotor abilities in young people. Methods: This is a cross-sectional study with 44 female participants (11.5 ± 1.5 years). Hormones were analyzed biochemically. Skeletal and somatic maturation were analyzed using anthropometry. The muscular power of the upper and lower limbs, body speed with change of direction, and speed of the upper limbs were verified. Results: Bone age was correlated with hormonal markers (estradiol: r = 0.58; p = 0.0007), (testosterone: r = 0.51; p = 0.005). Peak growth velocity correlated with estradiol (r = 0.51; p = 0.004). The power of the lower limbs (estradiol: r = 0.52; p = 0.006; testosterone: r = 0.42; p = 0.03) and of the upper limbs (estradiol: r = 0.51; p = 0.007; testosterone: r = 0.42; p = 0.02) had a positive correlation with hormone levels and had similar results with maturation. The analysis by artificial neural networks indicated that the maturation can predict the neuromotor performance between 57.4% and 76%, while the hormonal markers showed a potential of more than 95% for the foreshadowing of the neuromotor performance of the upper limbs. Conclusion: It was possible to conclude that the hormones had a relationship with maturational development and bone age in female subjects.

Anthropometric and physical fitness parameters versus specific performance tests in Brazilian field hockey athletes: a pilot study

Study aim: To investigate the correlation between anthropometric parameters, Sargent jump test, core muscles endurance and agility performance versus specific tests with and without a ball in female Brazilian field hockey athletes.

Material and methods: Nine professional female field hockey players (age: 27.4 ± 2.5 years) participated in this study. Body height, body weight, body fat percentage, Sargent jump test (SJT), shuttle run agility test (SR), core muscular endurance tests and sport-specific tests - repeated sprint ability test (RSA) and repeated sprint ability with the ball (RSAB) - were assessed in a randomized order.

Results: A moderate correlation was noted between SR and RSAB (r = 0.58, p = 0.09) and RSA (r = 0.60, p = 0.08). In addition, a moderate correlation was noted between percentage of body fat with RSAB (r = 0.59, p = 0.09) and with RSA (r = 0.72, p = 0.08). The other variables showed slight agreement or no agreement.

Conclusions: These results indicated that the SR could be implemented in training and evaluation programs of hockey athletes due to the correlation with specific tests. Thus, the percentage of body fat was the only anthropometric parameter that showed a correlation with the specific tests, revealing the importance of maintaining a proper percentage of body fat for better performance in hockey.