Análisis biomecánico comparativo de recepción a media altura entre jugadores profesionales y amateurs de fútbol / Análise biomecânica comparativa da captura em meia altura entre jogadores profissionais e amadores de futebol / Comparative biomechanical analysis of mid-height reception between professional and amateur soccer players

RESUMEN El fútbol es un deporte de varias acciones motrices, donde la recepción del balón se clasifica como una acción de control a diferentes alturas, velocidades y ángulos. El jugador debe tener la capacidad de receptar el balón para poder generar una acción diferente: un pase, tiro o driblar; su optimización implica mayores probabilidades de rendimiento técnico-táctico. En tal sentido, se planteó como objetivo de la investigación analizar biomecánicamente la técnica de la recepción a media altura en futbolistas profesionales y amateurs a partir de video análisis como método de medición. La investigación fue descriptiva-explicativa de orden correlacional, se analizan cuatro variables del movimiento motriz (D: distancia Recorrida; AM: aceleración máxima; VM: velocidad máxima y AF: amplitud de la articulación femorotibial) a través de video-análisis con Kinovea. Se estudiaron a cinco jugadores profesionales (grupo 1) y 15 de nivel amateur (grupo 2). Los futbolistas de nivel amateur presentaron una mayor media en todas las variables estudiadas, "D" (grupo 1: 72.17cm; grupo 2: 101.27cm; p=0.001), "AM" (grupo 1: 61.84m/s2; grupo 2: 101.73m/s2; p=0.000), "VM" (grupo 1: 8.18m/s; grupo 2: 12.55m/s; p=0.000) y "AF" (grupo 1: 62.6°; grupo 2: 75.2°; p=0.002), lo cual se comporta significativamente diferentes en todos los casos. El análisis biomecánico realizado a futbolistas profesionales y amateurs, en la técnica de recepción del balón a media altura, concluye que en los jugadores amateur requieren un mayor perfeccionamiento técnico, independientemente de su experiencia en competencias.

RESUMO O futebol é um esporte de várias ações motoras, onde a recepção da bola é classificada como uma ação de controle em diferentes alturas, velocidades e ângulos. O jogador deve ter a capacidade de receber a bola para poder gerar uma ação diferente: um passe, um chute ou um drible; sua otimização implica em maiores probabilidades de desempenho técnico-tático. Neste sentido, o objetivo da pesquisa era analisar biomecanicamente a técnica de recepção em meia altura em jogadores profissionais e amadores de futebol utilizando a análise de vídeo como método de medição. A pesquisa foi descritiva-explicativa de ordem correlacional, quatro variáveis de movimento motor (D: distância coberta; MA: aceleração máxima; MV: velocidade máxima e FA: amplitude da articulação femorotibial) foram analisadas através de vídeo-análise com Kinovea. Foram estudados cinco jogadores profissionais (grupo 1) e 15 jogadores amadores (grupo 2). Os jogadores de futebol de nível amador apresentaram uma média maior em todas as variáveis estudadas, "D" (grupo 1: 72,17cm; grupo 2: 101,27cm; p=0,001), "AM" (grupo 1: 61,84m/s2; grupo 2: 101. 73m/s2; p=0,000), "VM" (grupo 1: 8,18m/s2; grupo 2: 12,55m/s; p=0,000) e "AF" (grupo 1: 62,6°; grupo 2: 75,2°; p=0,002), que se comportam de forma significativamente diferente em todos os casos. A análise biomecânica realizada sobre jogadores profissionais e amadores de futebol, na técnica de recepção de bola em altura média, conclui que os jogadores amadores requerem um maior aperfeiçoamento técnico, independentemente de sua experiência em competições.

ABSTRACT Soccer is a sport of various motor actions, where the reception of the ball is classified as a control action at different heights, speeds and angles. The player must have the ability to receive the ball in order to generate a different action: a pass, shot or dribble; its optimization implies greater probabilities of technical-tactical performance. In this sense, the objective of the research was to biomechanically analyze the mid-height reception technique in professional and amateur soccer players using video analysis as a measurement method. The research was descriptive-explanatory of correlational order, four variables of the motor movement (D: distance covered; AM: maximum acceleration; VM: maximum speed and AF: amplitude of the femorotibial joint) are analyzed through video-analysis with Kinovea . Five professional players (group 1) and 15 amateur players (group 2) were studied. The amateur soccer players presented a higher mean in all the variables studied, "D" (group 1: 72.17cm; group 2: 101.27cm; p=0.001), "AM" (group 1: 61.84m/s 2 ; group 2: 101.73m/s 2 ; p=0.000), "VM" (group 1: 8.18m/s; group 2: 12.55m/s; p=0.000) and "AF" (group 1: 62.6°; group 2 : 75.2°; p=0.002), which behaves significantly different in all cases. The biomechanical analysis carried out on professional and amateur soccer players, in the technique of receiving the ball at mid-height, concludes that amateur players require greater technical improvement, regardless of their experience in competitions.

Monitoring of overtraining and motivation in elite soccer players

Abstract Aim: This study aimed to monitor the behavior of the overtraining and motivations dimensions, as well as to verify whether these dimensions correlate in the preparatory and competitive periods over the season. Methods: Professional soccer players (n = 32) answered the Stress and Recovery Questionnaire for Athletes (RESTQ-Sport 76) and the Sport Motivation Scale (SMS) during the preparatory and competitive periods. Results: Intrinsic amotivation and sport-specific recovery were lower in the competitive period than in the preparatory period. In the preseason, motivation presented a strong and negative correlation with overall recovery (p = 0.001; r = −0.75; r2 = 0.56) and sport-specific recovery (p = 0.001; r = −0.72; r2 = 0.52). The amotivation explained in 56% the variance of the results of the overall recovery and 52% of the sport-specific recovery. During the competitive phase, amotivation showed a strong and positive correlation with overall stress (p = 0.001; r = 0.70; r2 = 0.49) and sport-specific stress (p = 0.001; r = 0.79; r2= 0.62). The amotivation accounted for 49% of the variance in the results of the overall stress and 62% of sport-specific stress in soccer players. Conclusion: There are associations between overtraining and motivation during the investigated periods. Through longitudinal monitoring in professional soccer, it was verified that the dimensions of amotivation, overall recovery, and sport-specific stress could be related to the prevention symptoms of overtraining in a professional soccer team.

Comparisons of recovery, external and internal load by playing position and match outcome in professional soccer

AIMS: To compare the internal and external load and the recovery by playing position and the match outcome (wins, losses or draws) in professional soccer. METHODS: 23 male professional soccer athletes from a team of the first division of the Brazilian Championship took part into the study (age 26.1 ± 3.8 years old, weight 77.5 ± 5.0 kg, height 177.6 ± 5.1 cm). During the games, athletes were monitored by GPS and the variables of external loads were taken. Additionally, the session rating of perceived exertion (session RPE) and the perceived recovery scale (PRS) were collected 30 minutes and 40h after the end of the matches, respectively. RESULTS: The external load was greater on full-backs and defense midfielders (p<0.05). The full-backs cover higher total distances compared to attackers, and, compared to all the others positions, they have more stimuli > 20 km/h, covering higher distances >20 km/h; these stimuli makes them to perceive less recovered than defenders, defense and attack midfielders (p<0.05). Moreover, the defenders are those who cover lower distances by the minute and the defense midfielders are those who present the lower Peak Velocity (p<0.05). There were no significant differences between GPS variables, internal load and recovery. In addition, it was found a correlation between the external and the internal load (r=0.66; p=0.001). CONCLUSIONS: The GPS variables and the perceived recovery are influenced by the playing position, but not by the match outcome.(AU)

Mídia e a produção do sujeito jogador de futebol profissional / Media and the production of the professional soccer player

Este artigo tem como objetivo visibilizar e problematizar a constituição do sujeito jogador de futebol profissional na sociedade contemporânea. Como ferramenta metodológica, utilizou-se a análise das práticas discursivas provenientes de materiais midiáticos, articuladas com as regularidades de enunciados construídos pelos campos de conhecimento na produção dos modos de subjetivação deste profissional. Para a análise, selecionou-se o material proveniente da mídia impressa – Jornal Zero Hora, de Porto Alegre, especialmente, em um período que caracterizou-se pelo surgimento de um atleta jovem na categoria profissional. Como resultado, pode ser visibilizado que o jogador de futebol profissional é constituído na contemporaneidade pelos modos de subjetivação através dos imperativos dos investimentos técnicos e do lucro. O sujeito é submetido a intensa produção de metodologias dos campos de saber para aperfeiçoamento para um alto-rendimento e por consequência estar de acordo com as exigências de qualificações do mercado profissional...

This paper aims to visualize and problematize the constitution of the professional football player in contemporary society. As a methodological tool, it is used to analysis the discursive practices from media materials, articulated with the regularities of statements constructed by knowledge fields in the production of professional modes of subjectivity. It was selected for analysis, a media material came from diaries, especially the period characterized by the emergence of a young athlete in the professional category and have earned attention from media. As a result, it can be visualized that the contemporary professional soccer player is composed by the modes of subjectivity through the imperatives of technical investment and profit on body. It is remarkably seen the production of methodological knowledge on athletes, that turns to a high performance...

Elaboração de tabelas de percentis através de parâmetros antropométricos, de desempenho, bioquímicos, hematológicos, hormonais e psicológicos em futebolistas profissionais / Preparation of percentile tables through anthropometric, performance, biochemical, hematological, hormonal and psychological parameters in professional soccer players

INTRODUÇÃO: A carência de valores de referência de parâmetros antropométricos, de desempenho, bioquímicos, hematológicos, hormonais e psicológicos é uma limitação importante nas investigações envolvendo futebolistas profissionais. OBJETIVO: Elaborar tabelas de percentis para servirem como referencial de comparação para estudos posteriores. MÉTODOS: Foram utilizados 82 jogadores profissionais de futebol que foram avaliados aproximadamente 30 dias após o início da principal competição disputada pelas equipes. No primeiro dia de avaliação foram coletadas amostras de sangue (25mL) em jejum para determinação dos parâmetros hematológicos (eritrócitos, hemoglobina, hematócrito, volume corpuscular médio - VCM, hemoglobina corpuscular média - HCM, concentração de hemoglobina corpuscular média - CHCM, leucócitos, neutrófilos, eosinófilos, linfócitos, monócitos e plaquetas) e das concentrações de adrenalina, cortisol, creatina quinase, creatinina, noradrenalina, testosterona e ureia. Posteriormente, os atletas foram submetidos à avaliação antropométrica e psicológica. Em seguida, a avaliação da eficiência do sistema anaeróbio lático foi realizada em pista oficial de atletismo. No segundo dia foram realizadas as avaliações para determinação da eficiência do sistema anaeróbio alático e aeróbio. RESULTADOS: A distribuição de percentis (P0, P15, P30, P50, P70, P85 e P100) foi utilizada para apresentação dos resultados. CONCLUSÃO: A elaboração de tabelas de percentis pode ser utilizada como referencial de comparação para investigações posteriores.

INTRODUCTION: The lack of reference values of anthropometric, performance, biochemical, hematological, hormonal and psychological parameters is an important limitation in the investigations with soccer players. OBJECTIVE: To elaborate percentile tables to be used as comparison reference for further studies. METHODS: 82 professional soccer players were evaluated approximately 30 days after the beginning of the main competition played by their teams. On the first day of evaluation, fast blood samples were collected for measurement of hematological parameters (i.e. erythrocytes, hemoglobin, hematocrit, mean corpuscular volume - MCV, mean corpuscular hemoglobin - MCH, mean corpuscular hemoglobin concentration - MCHC, leukocytes, eosinophils, lymphocytes, monocytes and platelets) and of concentrations of adrenaline, cortisol, creatine kinase, creatinine, norepinephrine, testosterone and urea. Subsequently, the soccer players had their anthropometric characteristics and psychological parameters assessed. In addition, the evaluation of the lactic anaerobic system efficiency was performed on a 400-m track. On the second day, both the alactic anaerobic and aerobic system efficiency was measured. RESULTS: The percentile distribution (P0, P15, P30, P50, P70, P85 e P100) was used to present the results. CONCLUSION: The elaboration of the percentile tables can be used as comparison reference for further studies.

The Comparative Study on Food Consumption Patterns, Dietary Behavior, and Nutrition Knowledge of Korean Professional Soccer Players and Non-athletic Males / 대한지역사회영양학회지

This study was performed to compare food consumption patterns, dietary behavior, and nutrition knowledge between Korean professional soccer players and the non-athletic males. Data were collected from 53 soccer players working for Korean professional soccer clubs and 44 non-athletic males, using self-administered questionnaires. There were significant differences in food consumption frequency between two groups. Meats and eggs, fishes and shellfishes, sea weeds were consumed more frequently by the soccer players. The frequency scores of foods rich in iron, calcium, and protein were also higher in the soccer players compared with the non-athletes. Meanwhile, the consumption of alcohol was more frequent in the non-athletes. As for the cooking method, the soccer players showed higher preference for steaming/parboiling and consumed raw vegetables and fruits more frequently than the non-athletic males (p < 0.05). The average scores of soccer players on nutrition knowledge for basic nutrition and athletic nutrition were lower than the respective values of the non-athletic males. However, the soccer players showed better eating behaviors and dietary habits compared with non-athletic males (p < 0.001). They had well-balanced, regular diet and good habits for chronic disease prevention. No significant relationship could be observed with respect to nutrition knowledge and nutritional behavior. Moreover, the experience of getting nutrition information did not affect either nutrition knowledge score or nutritional habits score, except that for habits of chronic disease prevention in non-athletes. Therefore, it is suggested that more effective and practical nutrition education program be needed for promoting healthy eating habits and improving nutritional status in young males.

Efeito do treinamento físico específico nas respostas cardiorrespiratórias e metabólicas em repouso e no exercício máximo em jogadores de futebol profissional / Effect of specific exercise training in metabolic and cardiorespiratory responses at rest and maximum exercise in professional soccer players

O objetivo deste estudo foi analisar as alterações provocadas pelo treinamento físico específico (TFE) nas respostas cardiorrespiratórias e metabólicas de 16 jogadores de futebol profissional, com média de idade de 24,2 ± 3,6 anos. Todos os atletas foram avaliados antes e depois de quinze semanas de um programa de TFE, durante período competitivo. Os futebolistas foram submetidos a teste máximo em esteira rolante, utilizando-se o protocolo de Ellestad20. A resposta de freqüência cardíaca (FC) foi registrada por meio de um eletrocardiógrafo de 3 derivações simultâneas e a pressão arterial (PA), por meio de método auscultatório. A ventilação pulmonar (V E), o consumo de oxigênio (VO2), a produção de dióxido de carbono (VCO2) e a razão de troca respiratória (RER) foram calculados a partir de valores medidos por um sistema espirométrico computadorizado (Beckman) e a capacidade anaeróbia máxima, por meio da concentração sanguínea de ácido lático, utilizando-se analisador automático. O TFE não modificou significativamente a FC máxima (192 ± 8 vs. 186 ± 6bpm) e a PA sistólica máxima (196 ± 10 vs. 198 ± 8mmHg). A resposta ventilatória máxima foi significativamente aumentada (129 ± 19 vs. 140 ± 16L.min_1 [p< 0.05]), enquanto a capacidade aeróbia máxima não foi significativamente modificada (50,0 ± 6,0 vs. 53,0 ± 5,0ml.kg._1min_1) por esse treinamento. Ao contrário, a capacidade anaeróbia máxima aumentou significativamente (8,3 ± 0,2 vs. 9,8 ± 2,4mmol.L_1 [p< 0,05]). Concluiu-se: 1) o TFE não modificou as respostas de FC e PA no repouso e no exercício máximo; 2) a maior V E no exercício máximo associada a elevada concentração sanguínea de ácido lático demonstraram que o TFE utilizado nesse estudo foi caracterizado por exercícios predominantemente intensos; e 3) o TFE não representou estímulo adequado para aumentar a capacidade aeróbia máxima dos futebolistas.

The purpose of this investigation was to study the effect of specific training on cardiorespiratory and metabolic responses in sixteen male professional soccer players, aged 24.2 ± 3.6 years old. They were evaluated before and after fifteen weeks of specific training. All subjects were submitted to an exercise test on treadmill, using Ellestad's protocol. The heart rate was recorded by means of ECG, and the arterial blood pressure by auscultatory measurement. Oxygen uptake, carbon dioxide production, and pulmonary ventilation were measured by a Measurement Metabolic Cart (Beckman). Maximum anaerobic capacity was evaluated by blood lactate concentration, using an automated analyzer. Specific training did not modify the maximum heart rate (192 ± 8 vs. 186 ± 6 beats.min_1) and the maximum systolic blood pressure (196 ± 10 vs. 198 ± 8 mmHg). Maximum respiratory ventilation was significantly increased by specific training (129 ± 19 vs. 140 ± 16 L.min_1), whereas maximum aerobic capacity was not significantly increased (50 ± 6 vs. 53 ± 5 ml.kg._1 min_1 ofO2). On the other hand, maximum aerobic capacity improved significantly (8.3 ± 0.2 vs. 9.8 ± 2.4 mmol.L_1). Conclusion: 1) the specific training used in the present study did not modify heart rate and arterial blood pressure responses at rest and during maximum exercises; 2) improvement of maximum pulmonary ventilation and higher lactic acid concentrations during maximum exercise showed that the exercise training used in this study was predominantly characterized by intense exercise, and 3) specific training was not an adequate stimulus to improve maximum aerobic capacity of the soccer players.

Cardiopulmonary Response to Maximal Exercise Loading in Professional Soccer Players

BACKGROUND: Although maximal exercise stress tests are widely used in the athletic and medical fields, studies on professional soccer players are few. The purpose of our study is to observe the cardiopulmonary response to maximal exercise loading and the AT in professional soccer players. METHODS: Maximal exercise stress tests were carried out by a ramp protocol using a treadmill on 20 professional soccer players with a mean age of 25.2 years and with over 10 career years. The tests were also done on 21 college students majoring in physical education with a mean age of 19.4 years, which served as the control group. The AT was determined by the V-slope method. RESULTS: In the players, the VO2 max, VCO2 max and O2 pulse max were significantly larger than those in the control group, and the HR max was smaller for their ages. The VE max, VT max and RP max showed not much difference between the 2 groups but the VE max/VO2 max and VE max/VCO2 max were significantly lower in the players. The AT was larger in the players but the AT/VO2 max was essentially similar to that of the control group. CONCLUSION: Our study reveals that the professonal soccer players, despite their mean ages were approximately 6 years older than the subjects in the control group, had larger VO2 max and VCO2 max, and smaller HR max for their ages. The VE max was similar in both groups. This suggests that the players have higher aerobic capacity than the control group and exchange respiratiory gases more efficiently.