Flexibility of Ballet Dancers in COVID-19 Pandemic: A Prospective Observational Study in Portugal.

The aim of this study was to verify how dancers' flexibility work has developed during confinement through four assessment moments: before, during (two times), and after the lockdown period. The sample was formed by 18 dancers from the Porto Dance Conservatory (Portugal) with an average age of 11.4 ± 1.4 years and 1.4 ± 0.7 years of experience. To assess the passive and active flexibility level, we used seven of the International Gymnastics Federation's recommended tests using main joints (i.e., hips and spine). The first evaluation was performed before the pandemic situation began in a training environment, and the second and third evaluation were performed during the lockdown, in home environment, and in virtual trainings. Finally, the last evaluation was carried out in a training environment after returning to face-to-face activities and with several rules such a social distancing and mask use. The results showed that significant improvements were verified in the flexibility level of the dancers from the first to the fourth moment of evaluation. In the current study, no statistical significance was noted for the decreased values of functional asymmetry between the preferred and non-preferred lower limbs. These differences may have substantial relevance for dancers' harmonious body development.

The Effect of 16 Weeks of Lower-Limb Strength Training in Jumping Performance of Ballet Dancers.

Jumping ability is considered a determinant of performance success. It is identified as one of the predictors and talent identification in many sports and dance. This study aimed to investigate the effect of 16 weeks of lower-limb strength training on the jumping performance of ballet dancers. A total of 24 participants from the same dance school were randomly selected in the control group [CG; n = 10; aged 13.00 (1.49) years; 43.09 (9.48) kg and 1.53 (0.11) m] and the intervention group [IG; n = 14; aged 12.43 (1.45) years; 38.21 (4.38) kg and 1.51 (0.07) m], evaluated before and after the applied strength training program mainly using the body weight of each participant. Jump performance was assessed using MyJump2, a scientifically validated mobile phone app. Intergroup and intragroup comparisons were assessed, and the magnitude of change was calculated using the effect size (ES). While CG significantly decreased the relative power over time (p < 0.001, ES = -0.29: small), results from the intragroup comparisons suggest that IG significantly increased the countermovement jump (CMJ) height (p < 0.001, ES = 1.21: large), the relative force (p < 0.001, ES = 0.86: moderate), maximal velocity (p < 0.001, ES = 1.15: moderate), and relative power (p < 0.001, ES = 1.37: large). We concluded that a 16-week strength training program of lower limbs is an effective way to improve CMJ height in young dancers. Supplementary strength training appears to be the determinant for the improvement of the jumping performance of ballet dancers.

Morphological characteristics and biological maturation of Brazilian and Portuguese gymnasts / Características morfológicas y maduración biológica de gimnastas brasileñas y portuguesas

The morphological characteristics and biological maturation are among the more important factors in the performance in the Rhythmic Gymnastics. Thus, the aims of the present study were: (1) identify the training, morphological and biological maturation characteristics in elite Brazilian and Portuguese gymnasts; (2) compare these characteristics across groups. The Brazilian Portuguese National Team (13 gymnasts) were studied. Anthropometric and body composition measurements were performed. For analysis of biological maturation, the sexual (pubertal stages and age at menarche) and somatic (offset maturational) maturation were evaluated. The training data were collected by interviewing. For the statistical analysis, Mann-Whitney test was applied. The somatotype and calculation of its components were performed according to the Health-Carter method thought of the MER Goulding Software Development. Brazil and Portugal National Teams presented similar training volume and training onset, however Brazilian gymnasts had higher age and years of practice in Rhythmic Gymnastics than Portuguese gymnasts. Brazilian had higher body mass; height; lower limb length; triceps, subscapular and abdominal skinfolds; relaxed arm and thigh girths; and endomorphy somatotype component than Portuguese. The groups showed different somatotypes: Brazilian (endomorphic ectomorph) and Portuguese (balanced ectomorph), although without statistical significance. The groups demonstrated a delay in maturational development. Similar breast (stages 3 and 4) and pubic hair (stages 2 and 3) development were verified. In total, 84.6 % of gymnasts had reached menarche (15.9±2.6 years) and all gymnasts had reached the age at peak height velocity (14.9±1.2 years). The distance and age at peak height velocity were higher in Brazilian than in Portuguese.

Las características morfológicas y la maduración biológica se encuentran entre los factores más importantes en el rendimiento en la gimnasia rítmica. Por lo tanto, los objetivos del presente estudio fueron: (1) identificar las características de entrenamiento, morfológicas y maduración biológica en las gimnastas brasileñas y portuguesas de élite; (2) comparas estas características entre grupos. Se estudió la Selección Nacional Portuguesa y Brasileña (13 gimnastas). Se realizaron mediciones antropométricas y de composición corporal. Para el análisis de la maduración biológica, se evaluaron las etapas sexuales (etapas de pubertad y edad en la menarquia) y somáticas (edad en el pick de velocidad de altura). Los datos de entrenamiento fueron recolectados mediante entrevistas. Para el análisis estadístico, se aplicó la prueba de Mann-Whitney. El somatotipo y el cálculo de sus componentes se realizaron de acuerdo con el método de Health-Carter, pensado en el desarrollo de software MER Goulding. Los equipos nacionales de Brasil y Portugal presentaron un volumen de entrenamiento y un inicio de entrenamiento similares; sin embargo, las gimnastas brasileñas tenían mayor edad y años de práctica en gimnasia rítmica que las gimnastas portuguesas. Las brasileñas tenían mayor masa corporal; altura; longitud del miembro inferior; pliegues cutáneos del músculo tríceps, músculo subescapular y a nivel abdominal; circunferencia relajada del brazo y del muslo; y el componente somatotípico endomórfico que el portugués. Los grupos eran diferentes somatotipos: brasileñas (ectomórfico endomórfico) y portugués (ectomórfico equilibrada), aunque sin significación estadística. Los grupos demostraron un retraso en el desarrollo madurativo. Se verificó un desarrollo similar del seno (estadios 3 y 4) y del vello púbico (estadios 2 y 3). En total, el 84,6 % de las gimnastas alcanzaron la menarquia (15,9 ± 2,6 años) y el 92,3 % de las gimnastas alcanzaron su altura máxima con 17,4 ± 1,2 años. La distancia y la edad en la velocidad de alcance de la altura máxima fueron más altas en Brasil que en Portugal.

Judging in Rhythmic Gymnastics at Different Levels of Performance.

This study aimed to analyse the quality of difficulty judging in rhythmic gymnastics, at different levels of performance. The sample consisted of 1152 difficulty scores concerning 288 individual routines, performed in the World Championships in 2013. The data were analysed using the mean absolute judge deviation from the final difficulty score, a Cronbach's alpha coefficient and intra-class correlations, for consistency and reliability assessment. For validity assessment, mean deviations of judges' difficulty scores, the Kendall's coefficient of concordance W and ANOVA eta-squared values were calculated. Overall, the results in terms of consistency (Cronbach's alpha mostly above 0.90) and reliability (intra-class correlations for single and average measures above 0.70 and 0.90, respectively) were satisfactory, in the first and third parts of the ranking on all apparatus. The medium level gymnasts, those in the second part of the ranking, had inferior reliability indices and highest score dispersion. In this part, the minimum of corrected item-total correlation of individual judges was 0.55, with most values well below, and the matrix for between-judge correlations identified remarkable inferior correlations. These findings suggest that the quality of difficulty judging in rhythmic gymnastics may be compromised at certain levels of performance. In future, special attention should be paid to the judging analysis of the medium level gymnasts, as well as the Code of Points applicability at this level.