Relative age effect on the reaction time of soccer players under 13 years old

O efeito da idade relativa, que consiste na vantagem obtida pelo atleta nascido mais próximo ao início do ano de seleção, tem se mostrado uma variável importante para o processo de seleção de esportistas. Este estudo objetivou avaliar a influência da época de nascimento no tempo de reação de escolha de futebolistas presentes nas categorias de base (sub 13) de clubes profissionais futebol. Participaram 76 atletas com idade de 13,36 ± 0,45 anos. Os voluntários foram submetidos ao teste do TRE, e os resultados categorizados conforme o semestre de nascimento (S1 ou S2). Foi empregado o teste t para a comparação entre grupos, e análise de Correlação de Pearson para verificar a existência de associações entre as variáveis. Os resultados não indicaram diferenças entre os grupos no tempo de reação (r = 0,033 e p = 0,772) e no tempo de movimento (r = 0,0073 e p = 0,530). Concluiu-se que para essa população, a época de nascimento não influencia no desempenho dessa capacidade.

Registrador de sinais analógicos usando MP3 player portátil com entrada para voz

Neste trabalho se propôs a utilização do MP3 player portátil para gravação de sinal nãoáudio em sua memória, utilizando-se seu recurso para gravação de voz. Para avaliar a proposta, retirou-se o microfone de eletreto do MP3 player e em seu lugar injetou-se um sinal de FM, com portadora de áudio de 1200 Hz modulada pelo sinal de interesse. O sinal é gravado no aparelho em arquivo no formato WAV. Sua recuperação se fez usando um demodulador de FM a PLL cuja entrada é o sinal de FM captado nos terminais da bobina do fone de ouvido do MP3 player. Nos testes, usou-se sinal senoidal e sinal de eletrocardiograma. Embora a qualidade dos sinais de baixa freqüência precise ser melhorada, em geral os resultados apontam para a viabilidade da proposta. Fazem-se sugestões para melhorias e extensões do trabalho.

Análise comparativa dos sistemas de jogo e das ações técnicas realizadas pela seleção brasileira de futebol

Since its origin, soccer has been conquering followers all over the world. As a consequence of this cultural phenomenon, countless works are being done aiming to analyze the game systems and the fundamentals carried out by a team. The purpose of this paper is to analyze the Brazilian Soccer Team’s game systems and actions with ball possession in the 1958, 1962 and 2002 World Cup finals. Specifically, the paper analyzed the actions that occur during the match, such as control, dribble, pass, shot, foul and tackling. In order to achieve that, the Skout software (Barros et al., 2006) was utilized and, through it, all fundamentals carried out by the Brazilian team were identified and codified in a virtual field. The data from each match was transported into the Matlab® software, in which the zone of major action of each player was analyzed, represented by the main axis. The outcome showed that the game systems put into practice by the Brazilian team in the 1958 and 1962 World Cup finals didn’t present significant changes, nevertheless, regarding the 2002 final, there was a great difference. The Brazilian team got similar percentages in the technical actions carried out in the three World Cup finals analyzed, however, in absolute numbers, the passes, the shots and the dribbles decreased while the fouls increased.

A gênese do habitus e a construção da hexis corporal de bailarinos e jogadoras de futebol e suas implicações nos diferentes campos de atuação

This paper aims to show the beginning of habitus and the bodily hexis construction of male ballet dancer and female player soccer. Firstly, the habitus and the bodily hexis are established by the cultural inheritance of families (advices, likes, choices, prohibitions, and work divisions). After, they are restructured by the most diverse fields where this people act, mainly in the school, specifically at Physical Education classes (in the specialized places where these classes occur). Thus, it is possible to verify the success or the failure of their path lives and the possibility of a social ascent by the choice of these practices as professional career.

Kinesio Taping effects on knee extension force among soccer players

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito da utilização do coringa no treinamento em campo reduzido em jogadores de futebol universitário

Soccer is the most popular sport in Brazil and one of the most popular in the world. Within this context, the practice of university soccer has increased the number of practitioners. A methodology widely used in the training of high performance teams are games reduced field ( JCR). The objective of this study was to evaluate the intensity of physical effort of football players during a small side game, 4x4, check the correlation between [La], HR PSE and the players and the floater influence on the intensity of the small side game. We analyzed eight players of UNESP in Bauru mean age 21.2+1.5 years, weight 75.8+11.6 kg, height 1.77±8cm, body fat percentage 12.3+5.5%, VO2max 37.1 ml/kg/min. The training was performed in 4 x 6 min with an interval of between one minute for recovery. The [La] and PSE were collected between the second and third time and after the end of training, the HR was measured every five seconds throughout the training through the RS400 heart rate monitor. A training session player floater participation (4x4+1) and the other not (4x4). The results presented showed no correlation with the HR [La] and PSE. HR significantly different, being 157+10 in the game 4x4+1 and 146+13 in the game 4x4. The percentage of HRmax in the game with floater was 81.3% and 75.7% in the game without. The players were most of the time in a higher intensity in the JCR with a floater, 37.8% of playing time over 85% HRmax, and 22.5% of playing time over 85% of HRmax in the JCR without floater, demonstrating that the use of a floater player made the game more intense and efficient to increase the intensity of the game

Specific determination of maximal lactate steady state in soccer players

The aim of this study was to establish the validity of the anaerobic threshold (AT) determined on the soccer-specific Hoff circuit (AT(Hoff)) to predict the maximal lactate steady-state exercise intensity (MLSSHoff) with the ball. Sixteen soccer players (age: 16.0 +/- 0.5 years; body mass: 63.7 +/- 9.0 kg; and height: 169.4 +/- 5.3 cm) were submitted to 5 progressive efforts (7.0-11.0 km.h(-1)) with ball dribbling. Thereafter, 11 players were submitted to 3 efforts of 30 minutes at 100, 105, and 110% of AT(Hoff). The AT(Hoff) corresponded to the speed relative to 3.5 mmol.L-1 lactate concentration. The speed relative to 4.0 mmol.L-1 was assumed to be AT(Hoff4.0), and the AT(HoffBI) was determined through bisegmented adjustment. For comparisons, Student's t-test, intraclass correlation coefficient (ICC), and Bland and Altman analyses were used. For reproducibility, ICC, typical error, and coefficient of variation were used. No significant difference was found between AT test and retest determined using different methods. A positive correlation was observed between AT(Hoff) and AT(Hoff4.0). The MLSSHoff (10.6 +/- 1.3 km.h(-1)) was significantly different compared with AT(Hoff) (10.2 +/- 1.2 km.h(-1)) and AT(HoffBI) (9.5 +/- 0.4 km.h(-1)) but did not show any difference from LAn(Hoff4.0) (10.7 +/- 1.4 km.h(-1)). The MLSSHoff presented high ICCs with AT(Hoff) and AT(Hoff4.0) (ICC = 0.94; and ICC = 0.89; p <= 0.05, respectively), without significant correlation with AT(HoffBI). The results suggest that AT determined on the Hoff circuit is reproducible and capable of predicting MLSS. The AT(Hoff4.0) was the method that presented a better approximation to MLSS. Therefore, it is possible to assess submaximal physiological variables through a specific circuit performed with the ball in young soccer players.

Hamstrings-to-quadriceps strength and size ratios of male professional soccer players with muscle imbalance

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Brazilian soccer players and no-players adolescents: effect of the maturity status on the physical capacity components performance

The aim of this study was to compare the speed and the agility between Brazilian soccer players and non-players, regarding maturity status in adolescents 11-15 years old. Forty and two soccer players (age – 159.30±17.28 months old; weight – 48.45±9.96 kg; height – 1.53±0.10 m) and 45 non-players (age – 162.62±24.92 months old; weight – 48.30±8.35 kg; height – 1.54±0.12 m) participated of this study. Participants were classified by maturity status. On 2 different days with 1 week of differences between the assessments the participants were evaluated the agility, by Shuttle Run test, and the speed, by 30 m maximum speed test. The results showed that the maturity status was an influential factor in the performance with better results for individuals in a more advanced stage. The soccer practice does not seem to interfere in the performance of the physical capacity components analyzed, only effective when different maturity levels are involved in the analysis. It is also possible that late maturing boys selectively drop-out of soccer as age and sport specialization increase.

Análise do chute de bola parada em indivíduos não praticantes de futebol

In the soccer game, the player needs to be ready to attend the outlined requirements in differents extrategic moments. The fundamentals of soccer optimize their participation in a game, however, a correct execution of the movements can ensure their efficiency. From those fundamentals, we highlight the kick executed with the lower limbs characterized mainly by being an appeal of offensive played moving or stopped. Therefore, the objective of this review was to evaluate the kick's ability in the non- practitioners of this modality. Through a descripitive search, the objective followed by the protocol proposed by Mor-Cristian in 1979 was reached. The sample consisted of 48 individuals from both sexes, aged between 19 and 43 years old, students of Physics’ Education of a private University in the State of São Paulo - Brazil. The average of target 01 was 15.92 points, target 02 was 3.83, target 03 showed an average of 4.75 points and the target 04 had the average of 10.33. From the results we can observe that the target 01 have received the highest score over the other arcs. We conclude that the lower arches shown to be more likely to hit compared to the upper arches as being individuals who do not practice soccer.

Correlation between Hoff test performance, body composition and aerobic and anaerobic fitness in professional soccer players

Purpose The purpose of the study was to investigate a possible association between the distance covered in the Hoff test with parameters of maximal oxygen uptake (V_O2MAX), anaerobic threshold, anaerobic fitness, and body composition of professional adult soccer players. Methods Twenty-five professional soccer players (20 ± 3 years) participated in the study. On different days the athletes performed: a graded incremental exercise test in a laboratory to measure V_O2MAX; a specific soccer field test called the Hoff test; a running anaerobic sprint test (RAST); an incremental test on an oval circuit to determine the velocity relative to anaerobic threshold (VAnT) and an estimation of body composition. Results The average V_O2MAX corresponded to 4.1 ± 0.1 L min-1 (54.1 ± 1.2 mL kg-1 min-1 ). The average distance covered during the Hoff test was 1,442.4 ± 30.0 m. The distance covered during the Hoff test showed significant correlations with absolute and expressed in an appropriated scale V_O2MAX (r = 0.44, p = 0.02; r = 0.42, p = 0.02, respectively) while no significant differences were found with body composition, VAnT and RAST variables. Conclusions The present study demonstrated that the distance covered during the Hoff test has weak correlation with V_O2MAX determined in treadmill running, and no correlation with VAnT, body composition and RAST outcomes, probably due to the non-specificity of the proposed tests when associated with the Hoff test.

A Preliminary Study: Body Dysmorphic Disorder in Division I Women’s Collegiate Soccer Players

The prevalence of Body Dysmorphic Disorder (BDD) among collegiate athletes has not been clearly determined. The purpose of this study was to determine if there are symptoms of body dysmorphic disorder found in Division I women’s soccer players. The researcher hypothesized that there would be some symptoms found within the participants of sport and that there was a need to research this area further. The study consisted of four participants who participated in semi-structured interviews. The subjects were asked a series of questions from the Yale-Brown Obsessive Compulsive Scale Modified for Body Dysmorphic Disorder (BDD-YBOCS) to determine if they indicated any symptoms of BDD. The prevalence of symptoms of BDD found among these four participants was very low. There was only one athlete who scored high on the questions that could be questionable of whether the indicators or symptoms of BDD were present. In conclusion there was not enough evidence to support the research hypothesis. The sample used was not a clear representation of all Division I women’s soccer players. Further research is needed to determine if BDD symptoms are found among Division I women’s soccer players.