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The benefits of less repetitive practice schedules on motor learning are usually described in terms of greater demand for memory processes. The present study aimed to investigate the interactions between working memory and practice schedule and their effects on motor learning. Forty female participants had their WMC evaluated by the N-back test and were randomly allocated to either the variable random (VP) or the constant practice (CP) groups. In the acquisition phase, participants practiced 120 trials of a sequential key-pressing task with two goals: learning the relative and the absolute timing. Delayed retention and transfer tests occurred 24 h after the acquisition phase. Participants performed 12 trials of the motor task. Results showed that in the CP, learners with a high level of WMC presented better motor performance in the transfer test than learners with a low level of WMC. In the RP, no difference between WMC levels was found. Learners with a high level of WMC in the CP presented the same motor performance as learners in the RP regardless of the WMC level in the transfer test. In conclusion, learners with a high WMC could compensate for the poor working memory stimulation of a more repetitive practice schedule. The high WMC did not seem to exert an additional benefit when learners were well stimulated by a less repetitive practice schedule.

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Many results in motor learning have indicated that relative and absolute timing dimensions are modulated by factors that modify response stability among trials. One of these factors is the combination of constant and variable practices. Although many researchers have investigated the combination of practice schedules, these researchers have used measurements that do not assess performance and motor response separately. This study aimed to investigate the effect of different combinations of practice schedules on motor response stability during practice. Participants performed a sequential key-pressing task with two goals: (1) to learn the relative timing dimension and (2) the absolute timing dimension. Participants were assigned to one of two groups: constant-variable or variable-constant. Our findings indicate an influence of the increase in variability over the practice in the constant-variable group. Precisely, the increase in variability of total time in the second half (constant-variable group) of practice was followed by the maintenance of the same level of cross-correlate between absolute timing error and variability of total time. Finally, our findings support the hypothesis that practicing in a constant schedule favors the relative timing dimension of learning regardless of the order in which the constant practice is provided.

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Although the importance of practice has been evidenced in early studies of cross-limb transfer, the association between cross-limb transfer and practice organization remains unknown. The two primary means of organizing practice are constant practice (CP) and variable practice (VP). When the same generalized motor program governs the motor responses, VP produces better transfer than CP. Thus, we hypothesized that VP would generate a higher cross-limb transfer level than CP. We assigned 40 participants to CP or VP groups and conducted an experiment consisting of three phases: pre-test, practice, and transfer test. At pre-test, all participants practiced eight trials of a sequence key-pressing task with the non-dominant hand (NDH). After the pre-test, all participants performed a practice phase of 72 trials with the dominant hand, but CP and VP groups underwent their different practice schedules (CP or VP) such that the CP group practiced a sequence key-pressing task in one sequence, and the VP group practiced four different sequences randomly. On the transfer test all partcipants completed eight trials with the NDH 24 hours after the practice phase. The CP group showed better performance than the VP group on the transfer test, and we concluded that the effects of practice organization in cross-limb transfer are distinct from intra- and inter-task transfer such that the specificity of practice explained the benefits of CG.

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O objetivo deste estudo foi investigar o nível de conhecimento de graduados e graduandos em Educação Física sobre Aprendizagem Motora. Para isso, foi elaborado um questionário com 20 questões, sendo a primeira parte relacionada à identificação dos participantes e a segunda relacionada à Aprendizagem Motora. A análise foi feita com base na frequência de respostas dos participantes. A maioria dos participantes afirmou que sabiam o que era Aprendizagem Motora. No entanto, exibiram dificuldades em relação a algumas informações sobre a parte teórica. Além disso, os participantes apresentaram dificuldade em responder questões relacionadas aos fatores que influenciam a aprendizagem motora. Apesar do conhecimento sobre a temática contribuir efetivamente na forma pela qual o professor de educação física planeja e conduz as suas aulas, os participantes apresentaram impasses em responder às questões (AU).

The study aimed to investigate the level of knowledge of undergraduate and graduate students in physical education on Motor Learning. For this, a questionnaire with 20 questions was elaborated, the first part related to the identification of the participants and the second related to Motor Learning. The analysis was made based on the frequency of responses from the participants. Most of the participants stated that they knew what Motor Learning was. However, they showed difficulties about some information about the theoretical part. Also, the participants had difficulty in answering questions related to the factors that influence motor learning. Despite the knowledge about the theme effectively contributing to the way the physical education teacher plans and conducts his classes, the participants presented impasses in answering the questions (AU).

El objetivo del estudio fue investigar el nivel de conocimiento de estudiantes de pregrado y posgrado en educación física sobre el aprendizaje motor. Para esto, se elaboró un cuestionario con 20 preguntas, la primera parte relacionada con la identificación de los participantes y la segunda relacionada con el aprendizaje motor. El análisis se realizó en función de la frecuencia de las respuestas de los participantes. La mayoría de los participantes declararon que sabían lo que era el aprendizaje motor. Sin embargo, mostraron dificultades en relación con alguna información sobre la parte teórica. Además, los participantes tuvieron dificultades para responder preguntas relacionadas con los factores que influyen en el aprendizaje motor. A pesar de que el conocimiento sobre el tema contribuyó efectivamente a la forma en que el maestro de educación física planifica y dirige sus clases, los participantes presentaron dificultades para responder las preguntas (AU).

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Background: Mental fatigue is a psychobiological state caused by extended periods of cognitive effort, and evidence suggests that mentally fatigued athletes present impaired physical performance. Different ergogenic aids have been proposed to counteract the deleterious effects of mental fatigue, but whether brain stimulation can counteract mental fatigue is still unknown. This scenario is even more obscure considering the effects of these interventions (mental fatigue induction and brain stimulation) in a very experienced population consisting of master athletes. Method: Ten master swimmers (30 ± 6 years old and 14 ± 8 years of experience) participated in the study. They underwent four experimental conditions before an 800-m freestyle test: mental fatigue with brain stimulation; mental fatigue without brain stimulation; absence of mental fatigue with brain stimulation; and absence of mental fatigue and no brain stimulation. Mental fatigue was induced by a cognitively demanding Stroop Color Test, whereas stimulation was applied on the temporal cortex. After that, the athletes swan 800 m as fast as possible and provided their ratings of perceived exertion (RPE) every 200 m. Results: Mental fatigue was effectively induced, as evidenced by a greater fatigue perception and more errors in the last blocks of the cognitive task. Mental fatigue induction did not influence performance (time to complete the swimming trial) and RPE. Similarly, brain stimulation failed to change these two parameters, regardless of mental fatigue induction. Conclusion: The prolonged physical performance of experienced master athletes is not influenced, under the present conditions, by mental fatigue induction, cerebral stimulation, and their association.

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The primary motor cortex (M1) is one of the main cortical areas involved in motor learning. However, little is known about its differential role in the learning of the relative and absolute dimensions of motor skills. We investigated the role of M1 in the learning of the dimensions of a complex motor skill. Forty-eight participants practiced golf putting and were stimulated for 20 minutes with real or sham bihemispheric tDCS before acquisition. tDCS improved global performance from pre- to post-test. Only those with worse initial performance who were stimulated by tDCS showed a significant improvement in the skill's absolute dimension. No effects of tDCS were found for the relative dimension. Our results suggest that M1 has a distinct participation in the learning of the absolute dimension of complex motor skills, and tDCS effects are influenced by the learner's level of initial performance.

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Learning about the relative timing dimension of a motor skill is enhanced by factors that promote higher response stability between trials. Conversely, learning the absolute timing dimension is favored by lower trial-to-trial stability. The mental practice may increase response stability during acquisition since there is a low possibility of adjustments made between trials. Thus, this study aimed to test the hypothesis that some factors that increase response stability during the acquisition phase contribute to an enhanced relative timing dimension learning. Our hypothesis is that mental practice shows less relative timing error than the absence of practice. A sequential key-pressing task was practiced with two goals: learn (1) relative timing dimension and (2) absolute timing dimension. Participants were assigned to one of three groups: Physical, Mental, or No practice. The Physical group showed greater learning of both dimensions than the other two groups. The Mental group showed greater learning of relative timing dimension than the No practice group. The results suggest that mental practice produces increased stability, which in turn promotes learning of the relative timing dimension.

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RESUMO: Este estudo teve como objetivo analisar a lateralidade e a destreza manual em crianças com Transtorno do Espectro Autista (TEA). Do ponto de vista da motricidade humana, a lateralidade contribui para o processo de maturação motora. Figura-se entre as principais características do autismo o atraso nas habilidades motoras grossas e finas, com piora progressiva no quadro. Analisar o nível de lateralidade do indivíduo com TEA torna-se importante por possibilitar uma direção na intervenção motora com o intuito de melhorar a funcionalidade do autista e sua qualidade de vida. A amostra deste estudo foi composta por oito crianças, alunos de uma instituição de ensino pública, do sexo masculino, com idade média de 8,75±1,83 anos e diagnosticadas com TEA com base no DSM-V. Os resultados mostraram que os participantes do estudo parecem apresentar lateralidade destra e, também, melhor desempenho com a mão preferida em uma tarefa de destreza manual. Observou-se que, na tarefa que exigiu maior atenção e destreza, a diferença no desempenho das mãos foi significativa. Já na tarefa com menor demanda atencional e de destreza manual, o desempenho entre as mãos não foi significante, porém foi nesse momento que foram observados os maiores erros na execução. A motivação pode ser uma variável fundamental para o desempenho motor em tarefas que avaliam o tempo de execução. É importante uma maior ênfase no desenvolvimento da motricidade desses indivíduos durante a fase escolar para diminuir as dificuldades motoras e, consequentemente, melhorar a qualidade de vida, sensação de bem-estar, autonomia e interação social.

ABSTRACT: This study aimed to analyze laterality and manual dexterity in children with Autism Spectrum Disorder (ASD). From the point of view of human motor skills, laterality contributes to the motor maturation process. Among the main characteristics of autism is the delay in gross and fine motor skills, with progressive worsening in the condition. Analyzing the level of laterality of the individual with ASD becomes important because it allows a direction in the motor intervention in order to improve the functionality and quality of life of the autistic person. The sample of this study was composed of eight children, students of a public education institution, male, with an average age of 8.75 ± 1.83 years old and diagnosed with ASD based on the DSM-V. The results showed that the study participants seem to have right handedness and also better performance with the preferred hand in a manual dexterity task. It was observed that, in the task that demanded more attention and dexterity, the difference in hand performance was significant. In the task with the lowest attentional demand and manual dexterity, the performance between the hands was not significant; however, it was at that moment that the biggest mistakes in execution were observed. Motivation can be a fundamental variable for motor performance in tasks that assess execution time. It is important to emphasize the development of the motor skills of these individuals during the school phase to reduce motor difficulties and, consequently, improve quality of life, sense of well-being, autonomy and social interaction.

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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.

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The decrease in children motor competence, with a consequent reduction in the levels of physical activities and fitness, impacting health negatively, has affected children across countries. In addition to consistent intervention strategies, it is necessary to use appropriate instruments. The Körperkoordinationstest Für Kinder (KTK) is a reliable and low-cost motor coordination (MC) test used in several countries but lacking psychometric evidence in the Brazilian population. The present study investigates the factor structure of KTK in a Brazilian sample; and, compared four possibilities of calculating the factorial score of the test, precisely the sum of the scores, sum of the standard scores, weighted method, and the refined method. The participants of the study consisted of 565 volunteers (49.9% boys), from 5 to 10 (7.93 ± 1.51) years of age, with a body mass index (BMI) means of 17.04 (±2.81). The results showed that the KTK factor structure was adequate to the model for the total sample, by sex, and by age groups. However, the results did not confirm the invariance between sexes and age groups. Besides, our result showed that the sum of the raw scores of the subtests could be used as the factor score method in KTK. In the end, we conclude that the KTK is a valid test to measure the MC of Brazilian children and adolescents, with features that qualify it as a useful instrument both for research and for the practice.

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Transcranial Direct Current Stimulation (tDCS) is a neuromodulatory technique that has been used as an ergogenic aid in exercise/sports performance. However, little is known about its effects on highly-trained subjects, as athletes. The present study aimed to verify the effects of bi-hemispheric anodal tDCS (a-tDCS) on the performance of taekwondo athletes. Additionally, we investigated the persistence of the effects of the a-tDCS one hour after it. Nineteen Taekwondo athletes received active or sham bi-hemispheric a-tDCS over the primary motor cortex (M1). a-tDCS was delivered at 1.5 mA for 15 min. Athletes performed Countermovement Jumps (CMJ) and the Frequency Speed of Kick Test (FSKT) immediately (Mo1) and one hour after stimulation (Mo2). The athletes also reported their session-rating of perceived exertion (session-RPE). The total number of kicks (TK) was higher in sham than in the active a-tDCS condition (p < 0.01). In addition, TK was higher at Mo2 than at Mo1 (p < 0.05). Similarly, the session-RPE was higher in the a-tDCS condition (p < 0.05) and was greater one-hour post-stimulation (p < 0.01). No differences were found for CMJ performance (p > 0.05). Thus, bi-hemispheric a-tDCS worsens performance of taekwondo athletes, and the effect remains present even 1 h after the stimulation.

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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.

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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.

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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.

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É da natureza dos seres humanos apresentarem preferências na realização de tarefas do dia-a-dia. Esta preferência está associada à lateralidade. Um dos campos de estudo sobre a lateralidade é a assimetria lateral, que está presente tanto na dimensão da preferência quanto no desempenho. Objetivo: Este estudo teve como objetivo comparar a assimetria de força de preensão manual entre os sexos, e identificar se há associação entre assimetria de desempenho e assimetria de preferência. Método: A amostra foi composta por 50 estudantes universitários que realizaram teste de força de preensão manual máxima. Resultados: Os resultados indicaram que o os homens apresentaram valores absolutos maiores, maior índice de assimetria e menor consistência quando comparados às mulheres. Além disso, a mão preferida apresentou valores maiores de força em ambos os sexos. Conclusão: Em linhas gerais, sugere-se que fatores genéticos, sociais, culturais e sexo influenciam o comportamento motor dos indivíduos e, consequentemente, as assimetrias de desempenho.

It is of the nature of human beings to have preferences to performing daily tasks. This preference is associated with the laterality. One of the fields of the laterality study is lateral asymmetry, that is present in both preference and performance dimensions. Aim: This study aimed to compare manual grip strength asymmetry between genders and to identify if there is an association between asymmetry of performance and preference asymmetry. Method: The sample consisted of 50 university students who performed maximum manual grip strength tests. Results: The results indicated that the men had higher absolute values, higher Asymmetry Index and lower consistency when compared to the women. In addition, the preferred hand presented higher strength values in both sexes. Conclusion: In general, it is suggested that genetic, social, cultural and gender factors influence the motor behavior of the individuals and consequently the appearance of the lateral asymmetries.

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ABSTRACT The research aimed at comparing the decision making of volleyball coaches through visual search strategies (number and duration of visual fixations) based on their years of experience. The sample consisted of thirty-four volleyball coaches (n = 34) with a mean age of 32.5 ± 9.4 years. Thus, two groups were formed: beginners (2.8 ± 1.9 years of practice) and experienced (19 ± 7.2 years of practice). To assess the tactical knowledge related to aspects of decision-making, the coaches conducted the analysis of the end-attack scenes of the Declarative Tactical Knowledge Test in Volleyball. The results not related significant differences to the visual strategies, decision-making and declarative tactical knowledge in the analysis of the scenes between the two groups (p> 0.05), and the power of the effect ranged from small to moderate for the analyzed variables. In this context, it was noticed that the visual strategies used between the coaches with different times of experience were similar.

RESUMO A pesquisa objetivou a comparação da tomada de decisão de treinadores de voleibol por meio das estratégias de busca visual (número e duração das fixações visuais) em função dos seus anos de experiência. A amostra constituiu-se por trinta e quatro treinadores de voleibol (n=34) com idade média de 32,5 ± 9,4 anos. Assim, configuraram-se dois grupos: principiantes (2,8 ± 1,9 anos de prática) e experientes (19 ± 7,2 anos de prática). Para avaliação do conhecimento tático relacionado aos aspectos da tomada de decisão os treinadores realizaram a análise das cenas de ataque de extremidade do Teste de Conhecimento Tático Declarativo no Voleibol. Os resultados não apontaram diferenças significativas nas estratégias visuais, tomada de decisão e conhecimento tático declarativo na análise das cenas entre os dois grupos (p>0,05), sendo que o poder do efeito variou entre pequeno e moderado para as variáveis analisadas. Neste contexto, percebeu-se que as estratégias visuais utilizadas entre os treinadores com diferentes tempos de experiência foram semelhantes.

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ABSTRACT The association between contextual interference effect (CIE) and kinematic measures has been little investigated. The purpose of this study was to investigate the CIE on velocity and acceleration kinematic profiles of upper limb. Thirty-two subjects (23,7 ± 3,3 years) were assigned to groups of blocked practice (GPB) and random practice (GPA). The task consisted in achieve three targets in three specific sequences as quickly and accurately as possible. The study was designed in acquisition phase and transfer test. The variables of performance were reaction time, movement time, and response time and the kinematic variables were peak of speed, relative time to peak of speed, and number of peak acceleration points. The main findings showed that GPA showed lower movement time and response time than GPB. Regression analysis indicated that change in peak velocity during practice was associated to the change of the reaction time from practice to the transfer test. As peak velocity is a measure related to preprogramming, it is suggested that central control was essential to the CIE.

RESUMO Pouco se sabe a respeito da associação entre o efeito da interferência contextual (EIC) e medidas cinemáticas. O objetivo do presente estudo foi investigar o EIC nos perfis cinemáticos de velocidade e aceleração do membro superior. Vinte e dois participantes (23,7 ± 3,3 anos) foram alocados em dois grupos de prática: em blocos (GPB) e aleatória (GPA). A tarefa consistiu em acertar três alvos apresentados no monitor em três sequências pré-determinadas o mais rápido e preciso possível. O estudo foi dividido em fase de aquisição e teste de transferência. As variáveis de desempenho foram tempo de reação, tempo de movimento e tempo de resposta e as variáveis cinemáticas foram pico de velocidade, tempo relativo para o pico de velocidade e número de correções para alcançar o alvo. Os principais achados mostraram que o GPA apresentou menor tempo de movimento e de resposta do que o GPB. Análise de regressão indicou que a mudança observada ao longo da prática para a medida de pico de velocidade estava associada à mudança do tempo de reação da fase de aquisição para o teste de transferência. Como o pico de velocidade é uma medida associada à pré-programação, sugere-se que o controle central seja essencial para a observação do EIC.

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Abstract BACKGROUND There is aconsensus that repetition observed in constant practice producesminimalbenefits to the transfer of learning. OBJECTIVE The purpose of this study was to investigatein 3 experiments the effects of constant practicein transfer contexts. METHODOLOGY Participants were asked during acquisition phase, in all experiments, to press four keys sequentially with different requirements of absolute timing in a same relative timing structure. In the transfer tests, they were tested in a novel absolute timing criterion. RESULTS The results of experiment 1 and 2 showed that the relative timing structure was maintained only when the transfer required parameter scaling close to the parameter value practiced in acquisition. The transfer parameter that is far to the parameter practiced did not affect the movement parameterization. The result of experiment 3 showed that relative timing structure is disrupted in the transfer test when constant practice has high and low amount of practice. CONCLUSION Some specific aspects interfere in the transfer test when constant practice is experienced.(AU)

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AIMS: This study aimed to investigate the comparison between sex and manual aiming control in different cognitive and motor constraints of the task. METHODS: Eighty-four right-handed participants (42 women) performed 110 trials of a manual aiming task with a non-inking pen on a digitizing tablet. The aiming task required four different conditions of execution. The control condition appeared on the computer screen in 70% of the trials, and the other three conditions, (a) distractor, (b) inhibition of response and (c) higher index of difficulty, each appeared in 10% of the trials. RESULTS: Compared with women, men produced shorter movement and response times, as well as higher peak velocity in the control and distractor conditions. When the index of difficulty of the task increased, men produced only higher peak velocity. Women produced more corrective movements to achieve the target only in the control condition. CONCLUSION: Our results corroborate those of previous studies that indicate sex-specific response strategies when the sensory motor system is challenged by different task constraints.(AU)

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AIMS: The purpose of this study was to investigate the effects of the combination of constant and variable practice when both, motor program and parameters on absolute and relative dimensions of a task, are manipulated. METHOD: Twenty undergraduate students, aged between 19 and 24 years, participated in this study. Two groups practiced the task of pressing four keys of a numeric keyboard with total and relative times specified under constant conditions in the first part of the acquisition phase and under block conditions in the second part when one group varied parameters and another varied motor programs. RESULTS: Both groups improved parameters and motor program measures during the acquisition phase. In the retention test, the parameters variation resulted in higher accuracy on motor program measure that the variation of motor programs. CONCLUSION: Both combinations improve parameters and motor program accuracy. Moreover, the maintenance of GMP during the variation phase contributes to strengthening it.(AU)

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