Combination of narrow and wide bandwidth knowledge of performance in the acquisition of a complex sports motor skill.

OBJECTIVES: This study tested the effects of combining two bandwidth knowledge of performance (KP) on a complex sports motor skill. METHOD: Twenty-two elementary students were divided into combined wide and narrow bandwidth KP (WNG) and control group (CG). The task was the volleyball serve, whose goal was to hit the bull's eye center of a target lying on the floor on the opposite side of the court. The study was composed of a pre-test, acquisition phase and retention test, and had three measures (pre-test, intermediate test, and retention test) with 15 serves recorded each. The acquisition phase consisted of 252 trials. The WNG had a wide bandwidth KP in the first half of the acquisition phase and a narrow one in the second. The CG received KP in all trials. The effects of bandwidth KP were analyzed separately to infer parameters and skill structure learning. RESULTS: Both groups improved the skill structure from the first to the intermediate test, but only WNG also improved on the retention test. The parameters accuracy improved only on retention compared to the pre-test and intermediate test but had no difference between groups. CONCLUSION: Providing information using the bandwidth KP led to an initial engagement and prioritization of skill structure learning.

Executive Functions and Motor Adaptation to Predictable and Unpredictable Perturbations.

In this study, we aimed to investigate the influence of executive functions (EF) on motor adaptation. We compared the motor performance of adults with and without EF deficits. Those with EF deficits (n = 21) were individuals with attention deficit hyperactivity disorder (ADHD) under medical treatment, and those without EF deficits (n = 21) comprised a control group (CG) of participants who were also without neurological or psychiatric diagnoses. Both groups performed a complex coincident timing motor task and various computerized neuropsychological tests for assessing EF. To investigate motor adaptation, the motor task provided measures of absolute error (AE) and variable error (VE) to reflect, respectively, performance accuracy and consistency relative to the task goal. We used reaction time (RT) to measure planning time taken before starting the task. First, participants practiced until they reached a criterion of performance stabilization (prior to their exposure to motor perturbations). They were next exposed to fast and slow predictable and unpredictable perturbations. On all neuropsychological tasks, participants with ADHD scored more poorly than control participants (p < .05); participants with ADHD also performed worse than control participants on all motor measures, particularly under unpredictable perturbations (p < .05). Under slow perturbations, EF deficits, particularly attentional impulsivity, negatively affected motor adaptation while cognitive flexibility was related to performance improvement. Under fast perturbations, both impulsivity and fast reaction time were related to improvement in motor adaptation under both predictable and unpredictable perturbations. We discuss the research and practical implications of these findings.

Efeito das restrições no desempenho do saque do voleibol: o papel do nível de experiência / Effect of constraints on volleyball service performance: the role of the experience level

RESUMO O objetivo do estudo é investigar como o desempenho do saque do voleibol de sujeitos com diferentes níveis de experiência é influenciado pela interação de diferentes restrições. Participaram do estudo 36 voluntários do sexo masculino (16,44 ± 0,50 anos) alocados em dois grupos em função do nível de experiência. Os participantes executaram 10 tentativas do saque do voleibol em cada uma das quatro condições experimentais. Foram manipuladas uma restrição relacionada à dificuldade da meta e outra relacionada ao ambiente físico para execução da tarefa. O desempenho do saque por cima do voleibol foi avaliado por meio de uma lista de checagem do padrão de movimento e da precisão ao alvo. Os resultados demonstraram que o grupo experiente manteve o desempenho em todas as condições, enquanto o grupo inexperiente apresentou menor consistência da precisão nas condições com restrição física e pior escore do padrão de movimento na condição de maior dificuldade da meta em interação com a restrição física. O nível de experiência exerceu maior influência no desempenho do que as demais restrições. Uma possível explicação é que ela é uma restrição capaz de maximizar a forma como o sujeito explora as informações disponibilizadas pelas demais restrições.

ABSTRACT The aim of the study is to investigate how the volleyball service performance of subjects with different levels of experience is influenced by the interaction of different constraints. The study included 36 male volunteers (16.44 ± 0.50 years) allocated into two groups according to the level of experience. Participants performed 10 attempts of the serve volleyball in each of the four experimental conditions. One constraint related to the difficulty of the goal and another related to the physical environment for the execution of the task were manipulated. The performance of the overhand volleyball serve was assessed by means of a movement pattern checklist and of the accuracy to target. The experienced group maintained performance in all conditions, while the inexperienced group showed less consistency of accuracy in conditions with physical constraint and worse score of the movement pattern in the condition of greater difficulty of the goal in interaction with physical constraint. The level of experience had a greater influence on performance than the other constraints. One possible explanation is that it is a constraint capable of maximizing the way that the subject explores the information available by the other constraints

Motor competence in fundamental motor skills and sport skill learning: Testing the proficiency barrier hypothesis.

We investigated whether motor competence in fundamental motor skills influences sports motor skill learning. Motor competence in fundamental motor skills related to the overhead volleyball serve (i.e., throwing and volleying) was evaluated in 38 children (aged 9-10 yrs) and participants were divided into lower and higher motor competence groups. The groups practiced the volleyball serve under random or constant-random conditions during an acquisition phase and then assessed in pre-test, intermediate, and retention tests. A three-way repeated-measures ANOVA showed performance improvement from pre-test to retention test only for high motor competence groups in fundamental motor skills. Initial competence in fundamental motor skills influences sport skills learning and demonstrates a potential proficiency barrier to learning complex-sports motor skills.

Burnout and Coping Perceptions of Volleyball Players Throughout an Annual Sport Season.

Burnout is a psychological syndrome of reaction to chronic stress that occurs in athletes who feel exhausted by a sport activity that was previously pleasurable and enjoyable. One technique to prevent and control the syndrome is through coping, which is the ability to deal with stressful situations. In contrast to traditional cross-sectional approaches, this study aimed to investigate burnout and coping strategy characteristics over time and to analyze the relationship between burnout dimensions and coping strategies. Fifty-four high-level volleyball athletes (twenty-eight men and twenty-six women, age M = 25.57, SD = 4.72, range 18-35) completed paper-and-pencil measures of burnout and coping four times throughout a sport season. The Friedman test presented a significant increase in the reduced sense of athletic accomplishment (X2 = 20.58; p < 0.01) and sport devaluation (X2 = 19.83; p < 0.01) perceptions during the season. However, no coping differences were observed through the longitudinal analysis. Burnout dimensions showed a moderate inverse correlation to confidence/motivation at all measurement points during the season. Overall, the findings suggest that burnout perceptions increase as the season progresses, highlighting the relevance for the periodization of burnout prevention and control.

Aspectos motivacionais relacionados à prática do método pilates / Motivational aspects related to the practice of the pilates method

O presente estudo objetiva identificar os aspectos motivacionais que levam os indivíduos a praticar o Método Pilates. Foi aplicado o questionário IMPRAFE-54 em 52 indivíduos adultos e idosos. Variáveis como sexo, faixa etária e tempo de prática foram consideradas. Para as comparações de grupos foram realizados teste T e Mann-Whitney. Os resultados mostraram que, de uma forma geral, a amostra se motiva pelo fator saúde seguido pelo prazer. A variável saúde apresentou diferença significativa entre idosos e adultos. Mulheres adultas se motivam mais pelo domínio estética quando comparadas às idosas. Homens adultos se motivam mais pelo domínio saúde quando comparados aos idosos. Entender os aspectos motivacionais relacionados à prática do Método Pilates pode contribuir para uma melhor intervenção diretamente associada à satisfação dos praticantes.

This study aims to identify the motivational aspects that lead individuals to practice the Pilates Method. The IMPRAFE-54 questionnaire was applied to 52 adult and elderly individuals. Variables such as sex, age group and time of practice were considered. For group comparisons, the T test and the Mann-Whitney test were performed. The results showed that, in general, the sample is motivated by the health factor followed by pleasure. The health variable showed a significant difference between the elderly and adults. Adult women are more motivated by the aesthetic domain when compared to the elderly. Adult men are more motivated by the health domain when compared to the elderly. Understanding the motivational aspects related to the practice of the Pilates Method can contribute to a better intervention directly associated with the satisfaction of practitioners.

Enhanced Performance Stabilization Increases Performance Variability in a Virtual Interception Task.

Performing a motor task depends on the level of performance stabilization and movement control, and both aspects of motor behavior are related to motor learning (retention and transfer) and adaptation (predictable and unpredictable perturbations). Yet few studies have further investigated the underlying dynamics that may elicit these benefits. In this study, we investigated the effects of two levels of performance stabilization on motor performance and control while learning to intercept a virtual moving target. We randomly divided 40 participants of both sexes (Mage = 26.02 years, SD = 2.02) into a Stabilization Group (SG) and a Superstabilization Group (SSG). We considered the performance stabilized when a moving target was intercepted three times in a row and superstabilized when the same criterion was repeated six times. We analyzed outcome variables related to performance accuracy (absolute spatial error) and variability(coefficient of variation) and motor control (relative time to peak velocity-tPV% and its coefficient of variation) on both the first and last blocks of practice trials. Both groups showed comparable increases in performance accuracy from the first to the last block (p = .001, ηp2 = 1.00), but SSG presented higher variability than SG (p = .05, ηp2 = .70). Concerning motor control, both groups started the experiment with low tPV% and finished with comparably high tPV% and variability. Thus, although practicing two levels of performance stabilization led to similar performance accuracy and movement control, superstabilization resulted in higher performance variability with no loss of accuracy. Enhanced stabilization may increase the ability to adapt to environmental changes, but more research is needed to demonstrate this. These findings add to an understanding of the relationship between levels of performance stabilization and performance variability and may have implications for professional interventions (e.g. sports, rehabilitation) in considering the benefits of practice beyond performance stabilization.

Research on motor behavior in the year 2018 / Pesquisa na área de comportamento motor no ano de 2018

ABSTRACT Motor Behavior (MB) is the study of neuropsychological processes with regard to the motor response organization in terms of learning, control, and motor development. Three research sub-areas emerged from MB, that is, Motor Learning (ML), Motor Control (MC), and Motor Development (MD). The present study aimed at describing the intellectual production related to ML, MC and MD sub-areas in 2018, in addition to identifying the current profile of the MB area. The intellectual production of the MB sub-areas was organized according to stratum, type of task, and adherence to the journals of area 21 (CAPES). Fifty three articles on MB, published by 51 researchers, were found. All these studies were produced by the Graduate Programs of Physical Education in 2018. The distribution of the articles in sub-areas was represented as follows: 30.18% ML, 54.72% MC, and 15.10% MD. The MC sub-area had 86% of its articles published in the upper strata; the ML sub-area had 37%, followed by the MD sub-area with 13%. The average of the three sub-areas resulted in 83.02% of studies with simple tasks and only 16.98% with complex tasks. The greater number of publications with low adherence combined with the greater number of investigations with simple tasks seems to show the researchers' difficulty in approaching the knowledge produced in the MB area for undergraduate Physical Education students.

RESUMO A área de Comportamento Motor (CoM) investiga os processos neuropsicológicos da organização da resposta motora em termos de aprendizagem, controle e desenvolvimento motor, de onde emergiram. Este estudo teve como objetivo descrever a produção intelectual da área de Comportamento Motor (CoM), e as especificidades das suas subáreas de investigação denominadas Aprendizagem Motora (AM), Controle Motor (CM) e Desenvolvimento Motor (DM) produzidos pelos programas de Pós-graduação em Educação Física no ano de 2018. A produção intelectual nas subáreas do CoM foi organizada, por estrato, tipo de tarefa e aderência com os periódicos da área 21 da CAPES. Foram encontrados 53 artigos publicados por 51 pesquisadores. A distribuição dos artigos por subáreas foi representada por 30,18% AM, 54,72% CM e 15,10% DM. A subárea CM apresentou 86% de publicação dos artigos nos estratos superiores, a subárea AM com 37%, seguida da subárea DM com 13%. A média das três subáreas resultou em 83,02% de estudos com tarefa simples construída em laboratório e somente 16,98% com tarefa complexa. O maior número de publicações com baixa aderência aliado ao maior número de pesquisas com tarefas simples parece demonstrar a dificuldade dos pesquisadores de aproximar os conhecimentos produzidos na área de CoM com a formação de um corpo de conhecimento específico da Educação Física.

Controlling Degrees of Freedom in Learning a Taekwondo Kick.

To test Bernstein's degrees of freedom (DF) hypothesis, the authors analyzed the effect of practice on the DF control and interjoint coordination of a Taekwondo kick. Thirteen inexperienced and 11 expert Taekwondo practitioners were evaluated. Contrary to Bernstein's hypothesis, the inexperienced group froze the DF at the end of learning, reducing the joint range of motion of the knee. Moderate and strong cross-correlations between joints did not change, demonstrating that the interjoint coordination was maintained. The inexperienced group's movement pattern was similar to that of the group of experts, from the beginning of the learning process. Thus, even after years of practice, experts continue to explore the strategy of freezing DF. The DF freeing/freezing sequence strategy was explored during the learning process, suggesting that DF-freezing/freeing strategies are task dependent.

Freezing Degrees of Freedom During Motor Learning: A Systematic Review.

According to Bernstein, the central nervous system solution to the human body's enormous variation in movement choice and control when directing movement-the problem of degrees of freedom (DF)-is to freeze the number of possibilities at the beginning of motor learning. However, different strategies of freezing DF are observed in literature, and the means of selection of the control strategy during learning is not totally clear. This review investigated the possible effects of the class and objectives of the skill practiced on DF control strategies. The results of this review suggest that freezing or releasing the DF at the beginning of learning does not depend on the class (e.g., discrete skill class: football kick, dart throwing; continuous skill class: athletic march, handwriting) or objective of the skill (e.g., balance, velocity, and accuracy), in isolation. However, an interaction between these two skill elements seems to exist and influences the selection of the DF control strategy.

Motor learning and COMT Val158met polymorphism: Analyses of oculomotor behavior and corticocortical communication.

Differences in motor learning can be partially explained by differences in genotype. The catechol-O-methyltransferase (COMT) Val158Met polymorphism regulates the dopamine (DA) availability in the prefrontal cortex modulating motor learning and performance. Given the differences in tonic and phasic DA transmission, this study aimed to investigate whether the greater cognitive flexibility associated with the Val allele would favor the learning of movement parametrization, while the greater cognitive stability associated with the Met allele favors the acquisition of the movement pattern. Furthermore, we investigated if the genotypic characteristics impact visual scanning of information related to parametrization and to the movement pattern, and the level of cortical connectivity associated with motor planning and control. Performance and learning of a sequential motor task were compared among three genotypes (Val/Val, Val/Met, and Met/Met), as well as their oculomotor behavior and level of cortical coherence. The findings show that the cognitive flexibility promoted by the Val allele is associated with a better parametrization. The search for information through visual scanning was specific to each genotype. Also, a greater cortical connectivity associated with the Val allele was found. The combined study of behavioral, electrophysiological and molecular levels of analysis showed that the cognitive stability and flexibility associated with the COMT alleles, influence specific aspects of motor learning.

Focus of attention and online demonstration effects on temporal error and muscle activation / Efeitos do foco de atenção e demonstração online no erro temporal e na ativação muscular

Abstract The purpose of the present study was to examine whether there would be performance differences between external and internal focus of attention conditions and an online demonstration condition, and if these differences would be observed at a neuromuscular level through EMG analysis, in addition to traditional outcome measures. We hypothesized that under the demonstration condition participants would perform better than under external and internal focus conditions. We also hypothesized that demonstration condition would show smaller EMG activity than external and internal focus conditions. Furthermore, we hope to replicate the benefits of external focus in relation to internal focus, both in outcome and product measures. Six male participants performed a bilateral leg extension under internal focus of attention, external focus of attention and online demonstration conditions. Muscular contractions goal times were set for concentric muscle action (4 seconds) and eccentric muscle action (2 seconds). An electrogoniometer was used to record muscular activation (production measures), and temporal error was used to observe performance (outcome measures). Results showed that online demonstration condition obtained better performance than external focus condition and a reduced muscular activation. However, differences between internal focus and the other experimental conditions were not found. These findings advance in the understanding mechanisms underpining the focus of attention, such as proposed by Constrained Action Hypothesis.

Resumo O objetivo do presente estudo foi avaliar as diferenças no desempenho entre as condições de foco de atenção externo e interno e uma condição de demonstração online. Adicionalmente, se essas diferenças seriam observadas em um nível neuromuscular por meio da análise EMG, além das medidas de resultados tradicionais. Foi levantada a hipótese que sob a condição de demonstração os participantes teriam um desempenho melhor do que sob as condições de foco externo e interno. Também foi levantado a hipótese que a condição de demonstração apresentaria menor atividade EMG do que as condições de foco externo e interno. Além disso, esperava-se corrobora os benefícios do foco externo em relação ao foco interno, tanto nas medidas de resultado quanto de produto. Seis participantes do sexo masculino realizaram uma extensão de perna bilateral nas condições: foco de atenção interno, foco de atenção externo e condições de demonstração online. Os tempos de meta de contrações musculares foram definidos para ação muscular concêntrica (4 segundos) e ação muscular excêntrica (2 segundos). Um eletrogoniômetro foi usado para registrar a ativação muscular (medidas de produção) e o erro temporal foi usado para observar o desempenho (medidas de resultado). Os resultados mostraram que a condição de demonstração online obteve melhor desempenho do que a condição de foco externo e uma ativação muscular reduzida. No entanto, não foram encontradas diferenças entre o foco interno e as outras condições experimentais. Esses achados avançam no entendimento dos mecanismos que sustentam o foco de atenção, como o proposto pela Constrained Action Hypothesis.

Oculomotor behavior and the level of repetition in motor practice: Effects on pupil dilation, eyeblinks and visual scanning.

The benefits of less repetitive practice in motor learning have been explained by the increased demand for memory processes during the execution of motor skills. Recently, a new perspective associating increased demand for perception with less repetitive practice has also been proposed. Augmented information gathering and visual scanning characterize this higher perceptual demand. To extend our knowledge about mental effort and perceptual differences in practice organization, the association between oculomotor behavior and type of practice was investigated. We required participants to press four keys with different absolute and relative timing goals during the acquisition phase. An eye-tracker captured visual scanning of the skill's absolute and relative information displayed on the screen. Participants were tested 24 h after acquisition by a retention and transfer test. A higher level of both pupil dilation and amount of eyeblinks indicated an increased mental effort in less repetitive practice compared to more repetitive practice. Visual scanning of the skill's relative and absolute information was specific to the type of practice. The findings indicate many differences in oculomotor behavior associated with the practice schedule.

Self-Controlled Feedback and Learner Impulsivity in Sequential Motor Learning.

Many studies have attributed self-controlled feedback benefits associated with motor learning to learners' greater information processing during practice. However, individual learner characteristics like their impulsivity can also influence how people engage cognitively during learning. We investigated possible dissociations between the types of interaction in self-controlled knowledge of results (KR) and learner impulsivity levels in learning a sequential motor task. Ninety volunteers responded to the self-restraint section of the Barkley deficits in executive functioning scale, and those 60 participants with the highest ( n = 30) and lowest ( n = 30) impulsivity scores practiced a motor task involving sequential pressing of four keys in predetermined absolute and relative times. We further divided participants into four experimental groups by assigning the high- and low-impulsivity groups to two forms of KR-self-controlled absolute and yoked. Study results showed no interaction effect between impulsivity and self-controlled KR, and, contrary to expectation, self-controlled KR did not benefit learning, independently of impulsivity. However, low-impulsivity participants performed better than high-impulsivity participants on the absolute dimension of the transfer task, while high-impulsivity learners were better at the relative dimension. Cognitive characteristics of automatic and reflexive processing were expressed by the strategies used to direct attention to relative and absolute task dimensions, respectively. Low-impulsivity learners switched their attention to both dimensions at the end of practice, while high-impulsivity learners did not switch their attention or directed it only to the relative dimension at the end of the practice. These results suggest that the cognitive styles of high- and low-impulsive learners differentially favor learning distinct dimensions of a motor task, regardless of self-controlled KR.

Cathodal tDCS of the Left Posterior Parietal Cortex Increases Proprioceptive Drift.

In aiming movements the limb position drifts away from the defined target after some trials without visual feedback, a phenomenon defined as proprioceptive drift (PD). There are no studies investigating the association between the posterior parietal cortex (PPC) and PD in aiming movements. Therefore, cathodal and sham transcranial direct current stimulation (tDCS) were applied to the left PPC concomitantly with the performance of movements with or without vision. Cathodal tDCS applied without vision produced a higher level of PD and higher rates of drift accumulation while it decreased peak velocity and maintained the number of error corrections, not affecting movement amplitude. The proprioceptive information seems to produce an effective reference to movement, but with PPC stimulation it causes a negative impact on position.

Predictive factors of the attack efficacy: the case of the Brazilian women's Volleyball League champion team / Fatores preditivos da eficácia do ataque: o caso da equipe campeã da superliga feminina

Abstract The aim was to identify the predictive factors of the attack efficacy of the Brazilian women's League Champion team according to the level of performance of the opposing team.The sample was composed of the observation of 1137 attacks in 21 games of the 2015-2016 Brazilian women's Volleyball League champion team. The results were significant to identify the predictive factors of the attack efficacy against high (.2=110.562; .<0.00001), intermediate (.2=64.134; .<0.00001) and low (.2=62.137; .<0.00001) performance opponents. Thus, it is concluded that when playing against high- performance teams, powerful attack for position 6 and second attack tempo increase the chances of attack point; powerful attacks for position 1 and 5 reduce the chances of game continuation; and powerful attack for position 6 increases the chances of blocking. In addition, in games against intermediate-performance teams, reception that allows organized attack without all attack options reduces the chances of attack point and game continuation, while the reception effect did not seem to be a predictive factor of the attack efficacy in games against high- and low-performance opponents and, finally, in games against low-performance teams, powerful attack for position 1 reduces the chances of game continuation and attack blocking.

Resumo Objetivou-se identificar os fatores preditivos da eficácia do ataque da equipe campeã da superliga feminina conforme o nível de desempenho das equipes adversárias. A amostra compôs-se pela observação de 1137 ataques ocorridos em 21 jogos da equipe campeã da Superliga Feminina 2015-2016. Os resultados mostraram-se significativos na identificação dos fatores preditivos da eficácia do ataque em confrontos contra adversários de desempenho elevado (x.=110,562; p<0,00001), intermediário (x.=64,134; p<0,00001) e baixo (x.=62,137; p<0,00001). Assim, conclui-se que ao enfrentar equipes de elevado desempenho o ataque potente para a posição 6 e o 2º tempo de ataque aumentaram as chances de pontuar no ataque; os ataques potentes para a posição 1 e 5 reduziram as chances de ocorrer a continuidade do jogo e o ataque potente para a posição 6 aumentaram as chances de ocorrer o bloqueio. Além disso, em jogos contra equipes de desempenho intermediário a recepção que permitiu o ataque organizado sem todas as opções de ataque reduziu as chances de pontuar no ataque e de continuidade do jogo, enquanto que a eficácia da recepção não mostrou-se como fator preditivo da eficácia do ataque em jogos contra adversários de elevado e baixo desempenho; e, finalmente, em jogos contra equipes de baixo desempenho o ataque potente para a posição 1 reduziu as chances de ocorrer a continuidade do jogo e o bloqueio do ataque.

Discrete motor skill acquisition: effect of number of visual demonstrations / Aquisição de habilidade motora discreta: efeito do número de demonstrações

ABSTRACT This experiment investigated the effect of number of visual demonstrations on the acquisition of discrete motor skill. Seventy-four college students of both sex participated in this study. The participants observed a visual model twice or ten times. In the acquisition phase, the participants were asked to throw a dart with postero-anterior movement into a circle target until reach a learning criterion. In transfer tests no difference between groups was found in the analysis of score. However, ten demonstrations were more effective than twice as regards performance of the correct pattern of movement and the number of subjects who reached the performance criterion. The results indicate a similar effect of the both number of demonstrations in the performance and dart throwing learning and both conditions influence subject's capacity to detect relevant information to perform the task.

RESUMO Este experimento investigou os efeitos do número de demonstrações na aquisição de uma habilidade motora discreta. Setenta e quatro universitários, de ambos os sexos, participaram desse estudo. Os participantes observaram um modelo duas ou dez vezes. Na fase de aquisição, os participantes foram requisitados a lançar um dardo por meio de um movimento antero-posterior em um alvo circular até atingir um desempenho critério. Não foram identificadas diferenças na aprendizagem entre os grupos na análise do escore. Contudo, dez demonstrações estimularam melhor do que duas demonstrações no que diz respeito ao desempenho do padrão correto e ao número de sujeitos que atingiram o desempenho critério. Os resultados indicam um efeito similar de ambos os números de demonstrações no desempenho e aprenizagem do arremesso de dardo de salão e que ambas as condições estimularam a capacidade dos aprendizes de detectarem informações relevantes para desempenhar a tarefa.

Constant and random practice on learning of volleyball serve / Prática constante e aleatória na aprendizagem do saque do voleibol

Abstract The type of practice can influence what is learned from a motor skill. The aim of this study was to investigate the effects of the constant and random practice on the learning of Generalized Motor Program and parameters of the volleyball serve. The sample was composed of 20 children between 10 and 12 years old. The participants performed a pre-test whose score was adopted to counterbalance two groups (n=10), random practice and constant practice. During the acquisition phase, the random group performed 252 serves from three different positions, always indicated at the end of each serve, and the constant group performed all serves from only a specific position. The retention test showed that both groups learned the Generalized Motor Program, but random practice conducted to higher parameterization learning, resultant from the variable of practice. During practice of a sport motor skills, although the constant and random practice improve the learning of Generalized Motor Program, only the random practice improves learning of parameters of the motor skill.

Resumo O tipo de prática pode influenciar o que é aprendido de uma habilidade motora. Objetivou-se investigar os efeitos da prática constante e aleatória na aprendizagem do Programa Motor Generalizado e parâmetros do saque do voleibol. A amostra foi composta por 20 crianças entre 10 e 12 anos. Os participantes realizaram um pré-teste, cujo escore foi utilizado para contrabalançar dois grupos (n=10), prática constante e aleatória. Durante a fase de aquisição, o grupo aleatório realizou 252 saques de três posições diferentes, sempre indicada ao final de cada saque e o grupo controle realizou todos os saques somente de uma posição específica. O teste de retenção mostrou que ambos os grupos aprenderam o Programa Motor Generalizado, mas a prática aleatória conduziu para uma melhor aprendizagem dos parâmetros, resultante da prática variada. Durante a prática de habilidades motoras esportivas, apesar de as práticas constante e aleatória melhorarem a aprendizagem do Programa Motor Generalizado, somente a prática aleatória melhora a aprendizagem dos parâmetros da habilidade motora.