Explosive power of lower limbs in rhythmic gymnastics athletes in different competitive levels / Força explosiva de membros inferiores em ginastas da ginástica rítmica de diferentes níveis competitivos

Abstract The explosive power in Rhythmic Gymnastics shows itself in the great majority of movements and elements performed by the gymnasts, particularly in the jumps, which are essential corporal movements in this sport. The training directed to the development of jumping capacity presents a large quantity of exercises which aim to improve muscular power in the lower limbs and therefore the impulsion capacity. The vertical impulsion is an important measure used to calculate the explosive power of the lower limbs and is directly connected to the success that the gymnast will be able to achieve. Therefore, the aim of this study is to evaluate the height of two jumps in the RG (stag jump and Cossack jump) in contact mat Ergojump, which calculates the jump height in connection with the flight timing, executed by national level junior gymnasts and to compare them to the results of the Junior National Team - in total 30 junior gymnasts with 13.73 ± 0.17 years old. Furthermore, to compare the levels of explosive power of preferred lower limb (PLL) and non-preferred lower limb (NPLL) of all gymnasts in the study, in order to verify eventual functional asymmetries. For the statistical analysis we used Parametric Tests (t Test) and Nonparametric (Mann-Whitney Test and Wilcoxon Test). The gymnasts of the National Team achieved superior marks in 33.3% of the tests and 83.3% of the gymnasts of our sample did not present explosive power asymmetries. We conclude that the gymnasts of the National Team did not show the expected superiority in the tests, and the most of gymnasts presented a harmonious development of explosive power for both lower limbs, since they did not show functional asymmetries.

Resumo A força na Ginástica Rítmica manifesta-se na grande maioria dos movimentos e elementos realizados pelas ginastas, especialmente nos saltos, que são elementos corporais indispensáveis na prática da modalidade. O treino voltado para o desenvolvimento da habilidade de salto apresenta uma grande quantidade de exercícios que visam aumentar o grau de potência muscular de membros inferiores, e portanto, a capacidade de impulsão. A impulsão vertical é uma importante medida utilizada para mensurar a força explosiva de membros inferiores e está diretamente ligada ao sucesso que a ginasta poderá atingir. Deste modo, o presente estudo teve por objetivo avaliar a altura de dois saltos da Ginástica Rítmica (salto de corça e salto cossaco) através da plataforma de contato Ergojump, que calcula a altura do salto em função do tempo de voo, executados por ginastas juniores de nível nacional e comparar com resultados da Seleção Nacional Júnior – no total 30 ginastas, com idade média de 13,73 ± 0,17 anos. Além disso, comparar os níveis de força explosiva do membro inferior preferido (MIP) e membro inferior não preferido (MINP) de todas as ginastas do estudo, de modo a verificar possíveis assimetrias funcionais. Para a análise estatística recorremos aos Testes Paramétricos (Teste T) e não Paramétricos (Teste Mann-Whitney e Wilcoxon). As ginastas da Seleção Nacional alcançaram melhores resultados em 33% dos testes, deste modo concluímos que não conseguiram mostrar a superioridade esperada nos testes realizados. Além disso, verificamos que a maior parte das ginastas apresentaram um harmonioso desenvolvimento da força explosiva em ambos os membros inferiores, dado que e 83,3% das ginastas da amostra não demonstraram assimetrias funcionais.

Prediction of Vertical Jump Height from Anthropometric Factors in Male and Female Martial Arts Athletes

Background: Vertical jump is an index representing leg/kick power. The explosive movement of the kick is the key to scoring in martial arts competitions. It is important to determine factors that influence the vertical jump to help athletes improve their leg power. The objective of the present study is to identify anthropometric factors that influence vertical jump height for male and female martial arts athletes. Methods: Twenty-nine male and 25 female athletes participated in this study. Participants were Malaysian undergraduate students whose ages ranged from 18 to 24 years old. Their heights were measured using a stadiometer. The subjects were weighted using digital scale. Body mass index was calculated by kg/m2. Waist–hip ratio was measured from the ratio of waist to hip circumferences. Body fat % was obtained from the sum of four skinfold thickness using Harpenden callipers. The highest vertical jump from a stationary standing position was recorded. The maximum grip was recorded using a dynamometer. For standing back strength, the maximum pull upwards using a handle bar was recorded. Multiple linear regression was used to obtain the relationship between vertical jump height and explanatory variables with gender effect. Results: Body fat % has a significant negative relationship with vertical jump height (P < 0.001). The effect of gender is significant (P < 0.001): on average, males jumped 26% higher than females did. Conclusion: Vertical jump height of martial arts athletes can be predicted by body fat %. The vertical jump for male is higher than for their female counterparts. Reducing body fat by proper dietary planning will help to improve leg power.

Alterações na aptidão física de atletas de futebol infantil ao longo de um macrociclo de treinamento / Changes in physical fitness of u- 15 soccer players over macrocycles of training

O objetivo deste estudo foi avaliar a aptidão física das crianças de jogadores de futebol ao longo de um macro treinamento. A amostra foi composta por 16 atletas de futebol infantil, com altura média de 1,74 m (DP = 0,07) e peso corporal médio igual a 63 kg (DP = 6). Analisou-se a potência aeróbia (VO2max), velocidade (T30m), força explosiva de salto vertical (SV) em 4 diferentes tempos de macro (P1, P2, P3, P4). dados análise foi utilizada estatística descritiva e ANOVA de uma via com ajuste de Bonferroni. o principal os resultados foram os seguintes: o VO2max = 13% (P1xP3) e -3,8% (P3xP4); T30m = 4,1% (P1xP2), SV = 5,26% (P2xP3); Foi possível observar a consistência dos resultados com a metodologia proposta adotada, embora os resultados foram mostrados abaixo das expectativas.

The aim of this study was to evaluate children's physical fitness of footballers over a macro training. The sample consisted of 16 athletes from children's football, with average height of 1.74 m (SD = 0.07) and average body weight equal to 63 kg (SD = 6). We analyzed the aerobic power (VO2max), speed (T30m), explosive power of vertical jump (SV) in 4 different times of macro (P1, P2, P3, P4). Data analysis was used descriptive statistics and one-way ANOVA with Bonferroni adjustment. The main results were as follows: VO2max = 13% (P1xP3) and -3.8% (P3xP4); T30m = 4.1% (P1xP2), SV = 5.26% (P2xP3); It was possible to observe the consistency of results with the proposed methodology adopted, although the results have been shown below expectations.