US is a suitable tool to measure BF in the field testing of athletes and enables measurements of SAT with an accuracy and reliability not reached before. The sum of thicknesses (D or D) can be used to represent subcutaneous fat based on accurate measurements of uncompressed SAT thicknesses.

Objectives: Physical activity (PA) and adequate macro-and micronutrient intake have favourable influence on the bone status. The aim of this study was to analyse the relationships among PA, anthropometric data, dietary intake and ultrasound bone characteristics in children.Methods: 10-12 years old Hungarian children (N = 123, 59 girls, 64 boys) provided physical activity, diet, anthropometric and bone data. PA was measured with accelerometer (Actigraph GT3X+). Diet was evaluated with three-day, 24-hour food recall. Calcaneal quantitative ultrasound (QUS) bone parameters were registered with Sonost3000 bone densitometer.Results: Nutrition and anthropometry did not differ by gender. The values of broadband ultrasound attenuation (BUA) were significantly higher in boys. Girls spent significantly more time being sedentary, boys had greater light, moderate, vigorous, and moderate to vigorous physical activity (MVPA) levels. The children accumulated more than twice the suggested amount of public health guidelines for MVPA. QUS parameters correlated significantly with vigorous physical activity in boys, and with age, height, weight, fat percentage, and body mass index (BMI) for both genders. There was no significant relationship between nutrition and QUS; however, inadequate vitamin K intake correlated with less favourable bone parameters. Multiple linear regression analysis confirmed the importance of vigorous PA -speed of sound (SOS): β = 0.358, p = 0.006; BUA: β = 0.340, p = 0.007; bone quality index (BQI): β = 0.377, p = 0.002; vitamin K intake -SOS: β = 0.256, p = 0.025; BUA: β = 0.235, p = 0.033; BQI: β = 0.295, p = 0.007; BMI − SOS: β = 0.207, p = 0.064; BUA: β = 0.455, p < 0.001; BQI: β = 0.284, p = 0.008; and age -SOS: β = 0.450, p < 0.001; BUA: β = 0.318, p = 0.004; BQI: β = 0.444, p < 0.001).Conclusions: Changes in the characteristics of ultrasound bone parameters among 10-12 years old children mainly depended on the amount of intense PA, adequate vitamin K intake and anthropometric variables related to age.

The purpose of this study was to explore the association of the MCT1 gene Glu490Asp polymorphism (rs1049434) with athletic status and performance of endurance athletes. A total of 1,208 Brazilians (318 endurance athletes and 890 non-athletes) and 867 Europeans (315 endurance athletes and 552 non-athletes) were evaluated in a case–control approach. Brazilian participants were classified based on self-declared ethnicity to test whether the polymorphism was different between Caucasians and Afro-descendants. Moreover, 66 Hungarian athletes underwent an incremental test until exhaustion to assess blood lactate levels, while 46 Russian athletes had their maximum oxygen uptake ( ) compared between genotypes. In the Brazilian cohort, the major T-allele was more frequent in Caucasian top-level competitors compared to their counterparts of lower competitive level (P = 0.039), and in Afro-descendant athletes compared to non-athletes (P = 0.015). Similarly, the T-allele was more frequent in European athletes (P = 0.029). Meta-analysis of the Brazilian and European cohorts confirmed that the T-allele is over-represented in endurance athletes (OR: 1.48, P = 0.03), especially when Afro-descendant athletes were included in the meta-analysis (OR: 1.58, P = 0.005). Furthermore, carriers of the T/T genotype accumulated less blood lactate in response to intense effort (P < 0.01) and exhibited higher (P = 0.04) . In conclusion, the Glu490Asp polymorphism was associated with endurance athletic status and performance. Our findings suggest that, although ethnic differences may exist, the presence of the major T-allele (i.e., the Glu-490 allele) favours endurance performance more than the mutant A-allele (i.e., the 490-Asp allele).

Changes in the bone parameters among 7-19-year-old Hungarian children depended on age, anthropometric dimensions and the level of PA. The normative data could be used for monitoring QUS bone parameters in children, leading to more effective interventions for healthy bones.