Percorrer por autor "Silva, Manuel Coelho e"
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- Agreement between dual x-ray absorptiometers using pencil beam and fan beam: indicators of bone health and whole-body plus appendicular tissue composition in adult athletesPublication . Tavares, Óscar; Duarte, João; Costa, Daniela C.; Silva, Paulo Sousa e; Martinho, Diogo V.; Lus, Leonardo; Duarte-Mendes, Pedro; Santos, João Valente dos; Conde, Jorge; Casanova, José; Cyrino, Edilson S.; Silva, Manuel Coelho eOBJECTIVE: The current study was aimed to examine intra-individual variation on indicators of bone health in addition to whole-body plus appendicular tissue measurements using two concurrent assessments based on pencil beam and fan beam dual energy X-ray absorptiometry (DXA) systems in adult athletes from several sports. METHOD: Thirty-two male participants (27.6±10.1 years) were measured on anthropometry including multifrequency bioelectric impedance and air-displacement plethysmography. Bone mineral content (BMC), bone area, fat and lean soft tissue were derived using pencil beam (Lunar DPX-MD+) and fan beam (Lunar iDXA) absorptiometry. Bone mineral density (BMD) was obtained for the femoral neck, trochanter and triangle of ward. Finally, the right thigh was defined as a region of interest (ROI). Analyses comprised intra-class correlation (ICC), Effect size (d) from mean differences of repeated measurements, coefficient of variation (CV) RESULTS: ICC were >0.900 for all measurements. Intra-individual differences were large for BMC (d=1,312; CV=2,7%), bone area (d=1,761; CV=2,7%), fat tissue (d=1,612; CV=11%) and all indicators of appendicular lean soft tissue (d=1,237-1687; CV=2,0-4,1%). A very large difference (d=4,014; CV=8.4%) was diagnosed for lean soft tissue of the ROI. CONCLUSION: Although differences among concurrent instruments for BMC and bone area, the effect size of mean differences was negligible for BMD. Fat and lean soft tissue derived from DXA should be interpreted as reference values (not criterion) due to equipment-related variation, more apparently in the ROI values.
- Associação entre a relação 2D:4D e o desempenho desportivo em atletas. Uma revisão sistemática e meta-análisePublication . Bernardino, Vanda; Rebelo, André; Cruz, João; Vaz, Vasco; Santos, João Valente dos; Silva, Manuel Coelho e; Duarte-Mendes, PedroIntrodução: A identificação de jovens atletas talentosos no desporto de alto rendimento requer uma abordagem multidisciplinar que considere a complexa cominação de características genéticas, psicológicas, físicas, técnicas e táticas, sendo o rácio 2D:4D uma possível ferramenta adicional. Objetivo: Este estudo visa analisar, através de uma revisão sistemática e meta-análise, as relações entre o rácio 2D:4D e várias capacidades físicas em atletas de diferentes idades e níveis competitivos. Metodologia: A pesquisa bibliográfica foi realizada nas bases de dados PubMed, Scopus, Web of Science e SPORTDiscus, com os artigos recuperados sendo importados para o software Cadima para otimizar a síntese de evidências e garantir rigor metodológico. A qualidade dos estudos foi avaliada utilizando a lista de “Downs e Black”, e a análise estatística da meta-análise foi efetuada com o modelo de Efeitos Aleatórios para considerar a variabilidade entre os estudos. Resultados: Foram selecionados 67 estudos para a revisão da literatura, e 19 estudos, que avaliaram 3581 rácios 2D:4D, foram incluídos na meta-análise. Os principais resultados revelaram diferenças significativas entre homens e mulheres, com os homens apresentando valores de 2D:4D tipicamente mais baixos. Além disso, os atletas tendem a ter rácios 2D:4D inferiores em comparação com os não-atletas. Conclusões: Foram identificadas associações negativas entre o rácio 2D:4D e a capacidade aeróbia, VO2máx, potência anaeróbia e força muscular, enquanto que as relações com velocidade, capacidade anaeróbia e flexibilidade mostraram-se menos consistentes.
- Body composition and grip strength constraints in elite male rink-hockey players of contrasting ethnicityPublication . Ferraz, António; Santos, João Valente dos; Duarte-Mendes, Pedro; Nunes, Célia; Victorino, Samuel; Silva, Manuel Coelho e; Travassos, BrunoRink hockey is a highly specialized and physiological demanding sport with sparse research regarding the game and athletes’ characteristics. A cross-sectional study was developed to characterize the body composition and grip strength of elite male rink hockey players and to establish the relationship between ethnicity on body composition and grip strength. A sample of 100 elite rink-hockey athletes aged 26.59 ± 6.02 participated in the study, comprised of 69 Caucasian male adults aged 27.58 ± 6.44 years and 31 Black African male adults aged 24.39 ± 4.27. Body composition was assessed by anthropometric measurements. Static grip strength was assessed with an adjustable dynamometer. Multiple regression analysis was applied to understand which variables constraints body fat percentage (BF) and grip strength. Body mass showed an average of 76.36 ± 9.18 kg for 175.80 ± 5.87 cm of height and BF% of 10.82 ± 5.07%. Maximal right grip strength was 50.91 ± 6.26 kg and 50.27 ± 6.23 kg for left grip strength. Four predictors accounted for 70.01% of the variance of BF%: abdominal circumference (p < 0.001), right thigh circumference (p < 0.001), right calf circumference (p = 0.001) and ethnicity (p = 0.016). Three predictors accounted for 13.1% of the variance of right grip strength: ethnicity (p = 0.013), chronological age (p = 0.024) and right distal thigh circumference (p = 0.014). Results suggest that elite rink hockey athletes have a specific anthropometric identity, which at the elite level may lead to reduced body fat and greater handgrip strength. Ethnicity seems to predict body fat and grip strength in elite rink hockey athletes.
- Intra-observer reproducibility and inter-observer agreement of Fels skeletal age assessments among male tennis players 8–16 yearsPublication . Silva, Paulo Sousa e; Silva, Manuel Coelho e; Celis-Moreno, Jorge M.; Costa, Daniela C.; Martinho, Diogo V.; Ribeiro, Luís P.; Oliveira, Tomás; Santos, João Gonçalves; Tavares, Óscar; Castanheira, Joaquim M.; Pereira, Telmo; Conde, Jorge; Cayolla, Ricardo R.; Duarte-Mendes, Pedro; Myburgh, Gillian K.; Cumming, Sean P.; Malina, Robert M.Background Skeletal age (SA) is an estimate of biological maturity status that is commonly used in sport-related medical examinations. This study considered intra-observer reproducibility and inter-observer agreement of SA assessments among male tennis players. Methods SA was assessed with the Fels method in 97 male tennis players with chronological ages (CA) spanning 8.7–16.8 years. Radiographs were evaluated by two independent trained observers. Based on the difference between SA and CA, players were classified as late, average or early maturing; if a player was skeletally mature, he was noted as such as an SA is not assigned. Results The magnitude of intra-individual differences between repeated SA assessments were d = 0.008 year (observer A) and d = 0.001 year (observer B); the respective coefficients of variation were 1.11% and 1.75%. Interobserver mean differences were negligible (t = 1.252, p = 0.210) and the intra-class correlation coefficient was nearly perfect (ICC = 0.995). Concordance of classifications of players by maturity status between observers was 90%. Conclusion Fels SA assessments were highly reproducible and showed an acceptable level of inter-observer agreement between trained examiners. Classifications of players by skeletal maturity status based on assessments of the two observers were highly concordant, though not 100%. The results highlight the importance of experienced observers in skeletal maturity assessments.
- Skeletal age assessed by Greulich-Pyle: Intra-observer and inter-observer agreement among male pubertal tennis playersPublication . Celis-Moreno, Jorge M.; Martinho, Diogo V.; Silva, Manuel Coelho e; Fragoso, Isabel; Ribeiro, Luís P.; Gouveia, Élvio R.; Oliveira, Tomás; Santos, João Gonçalves; Tavares, Óscar ; Cayolla, Ricardo R.; Konarski, Jan M.; Malina, Robert M.; Myburgh, Gillian K.; Cumming, Sean P.; Sherar, Lauren B.; Duarte-Mendes, PedroThe assessment of biological maturation is a central topic in pediatric exercise sciences. Skeletal age (SA) reflects changes in each bone of the hand and wrist from initial ossification to the adult state. This study examined intra-observer and inter-examiner agreement is Greulich-Pyle (GP) assessments of SA in 97 male tennis players 8.6–16.8 years of age. Two observers independently examined all films on two occasions using the GP method. The SA of each bone was evaluated. The mean and median of SAs assigned for each bone was the individual SA for each participant. The calculation was exclusively based on the bones that were not skeletally mature. Intra-observer mean differences were significant for several bones with better results by the experienced examiner (observer B). Comparisons between SA values of the two independent observers indicated significant differences for the ulna, metacarpals II and III, and distal phalanx V. Nevertheless, the magnitude of the bone-specific differences was small, perhaps trivial. Differences in individual SA values of the tennis players based on the non-mature bones of the hand-wrist were negligible based on the mean (0.04±0.39, t = 0.321, p = 0.749) or the median (0.05±0.58, t = 0.007, p = 0.994). Nevertheless, the current study confirmed examiners as a source of error in the estimation of SA using the Greulich-Pyle method and highlighted the importance of calculating SAs based on non-mature bones among adolescent players.