The Second-to-Fourth Digit (2D:4D) Ratio of Male Combat Athletes is Associated with the Choice of Sport

The second-to-fourth-digit (2D:4D) ratio has been widely used as a putative marker of prenatal exposure to testosterone in health, behavioral and sport sciences, but it has only been used few times regarding combat athletes. This study involved 200 male elite combat athletes (Olympic wrestling, kickboxing, judo, taekwondo and karate) and 179 males not participating in any sports. The lengths of the index finger (2D) and ring (4D) finger were measured using computer-assisted image analysis (AutoMetric 2.2 software). The 2D:4D ratio of combat athletes was significantly lower than that of the controls. Moreover, a lower 2D:4D ratio was found among wrestlers, judo athletes and kickboxers than in the control group, and a higher 2D:4D ratio was found, but with borderline significance, among karate and taekwondo athletes. Moreover, multivariate analysis adjusted for age showed that judo, Olympic wrestling and kickboxing athletes combined had 2D:4D ratios significantly lower (by 0.035 on average) than those of the rest of the subjects and that karate and taekwondo athletes together had 2D:4D ratios significantly higher (by 0.014 on average) than those of the rest of the subjects. The research results and literature review indicate that knowledge about the functional meaning of the 2D:4D ratio is still too fragmentary and it is too early to use the 2D:4D ratio in the selection of sport talent; however, it may be a useful criteria when screening prospective athletes to be recruited to a team. That is why 2D:4D reference values should be defined for particular sports.

Multivariate Profiles of Selected versus Non-Selected Elite Youth Brazilian Soccer Players

This study determined whether a multivariate profile more effectively discriminated selected than non-selected elite youth Brazilian soccer players. This examination was carried out on 66 youth soccer players (selected, n = 28, mean age 16.3 ± 0.1; non-selected, n = 38, mean age 16.7 ± 0.4) using objective instruments. Multivariate profiles were assessed through anthropometric characteristics, biological maturation, tactical-technical skills, and motor performance. The Student’s t-test identified that selected players exhibited significantly higher values for height (t = 2.331, p = 0.02), lean body mass (t = 2.441, p = 0.01), and maturity offset (t = 4.559, p < 0.001), as well as performed better in declarative tactical knowledge (t = 10.484, p < 0.001), shooting (t = 2.188, p = 0.03), dribbling (t = 5.914, p < 0.001), speed – 30 m (t = 8.304, p < 0.001), countermovement jump (t = 2.718, p = 0.008), and peak power tests (t = 2.454, p = 0.01). Forward stepwise discriminant function analysis showed that declarative tactical knowledge, running speed –30 m, maturity offset, dribbling, height, and peak power correctly classified 97% of the selected players. These findings may have implications for a highly efficient selection process with objective measures of youth players in soccer clubs.

The association of gene polymorphisms with athlete status in ukrainians

Athletic performance is a polygenic trait influenced by both environmental and genetic factors.

OBJECTIVE

To investigate individually and in combination the association of common gene polymorphisms with athlete status in Ukrainians.

METHODS

A total of 210 elite Ukrainian athletes (100 endurance-oriented and 110 power-orientated athletes) and 326 controls were genotyped for ACE I/D, HIF1A Pro582Ser, NOS3 -786 T/C, PPARA intron 7 G/C, PPARG Pro12Ala and PPARGC1B Ala203Pro gene polymorphisms, most of which were previously reported to be associated with athlete status or related intermediate phenotypes in different populations.

RESULTS

Power-oriented athletes exhibited an increased frequency of the HIF1A Ser (16.1 vs. 9.4%, P = 0.034) and NOS3 T alleles (78.3 vs. 66.2%, P = 0.0019) in comparison with controls. Additionally, we found that the frequency of the PPARG Ala allele was significantly higher in power-oriented athletes compared with the endurance-oriented athletes (24.7 vs. 13.5%; P = 0.0076). Next, we determined the total genotype score (TGS, from the accumulated combination of the three polymorphisms, with a maximum value of 100 for the theoretically optimal polygenic score) in athletes and controls. The mean TGS was significantly higher in power-oriented athletes (39.1 ± 2.3 vs. 32.6 ± 1.5; P = 0.0142) than in controls.

CONCLUSIONS

We found that the HIF1A Ser, NOS3 T and PPARG Ala alleles were associated with power athlete status in Ukrainians.