This study investigated compound spatial and temporal measures of interpersonal interactions purported to constrain the emergence of affordances for passing direction in the team sport of futsal. For this purpose, attacker-defender interactions in 37 sequences of play from a futsal competition in which 24 male professional players participated (M=30.04 years, SD=4.10) were filmed and analysed using TACTO software. Relative angle data were used as measures to study coordination tendencies that emerged between players during performance. Results showed that the direction for a pass emerged from relative angles between: (1) the vector from a ball carrier to ball receiver and the vector from the ball carrier to the nearest defender (70°) (p<0.01) and (2) the vector from a ball carrier to ball receiver and the vector from the ball carrier to a ball receiver's nearest defender (31°) (p < 0.01). Furthermore, passing direction was also constrained by temporal information from the emergence of both angles, since the pass was performed to attacker-defender dyads with the highest velocities of these angles (p < 0.05). Results suggested that decisions on selecting the direction of a pass in the team sport of futsal emerged at critical values of these key compound motion measures.

The aim of this study was to investigate the effects of knowledge of results (KR) frequency and task complexity on motor skill acquisition. The task consisted of throwing a bocha ball to place it as close as possible to the target ball. 120 students ages 11 to 13 years were assigned to one of eight experimental groups according to knowledge of results frequency (25, 50, 75, and 100%) and task complexity (simple and complex). Subjects performed 90 trials in the acquisition phase and 10 trials in the transfer test. The results showed that knowledge of results given at a frequency of 25% resulted in an inferior absolute error than 50% and inferior variable error than 50, 75, and 100% frequencies, but no effect of task complexity was found.

The aim of this study was to investigate the influence of the goalkeeper as an outfield player on defensive subsystems in the team sport of futsal. For this purpose, all sequences of play involving the goalkeeper (n = 65), and the sequences without a goalkeeper (controls) (n = 11), were selected from digital video footage of a futsal competition, and analysed using TACTO software. The defensive area, attacker-defender distance, and interception distance were used to examine players' coordination tendencies as a team in completion of successful and unsuccessful passes and shots. Results showed that each team reduced its defensive area as well as its variability in situations where the goalkeeper acted as an outfield player. This finding implies that it was an effective defensive strategy because it led to emergence of more unsuccessful passes. It was also observed that the goalkeeper acting as an outfield player was an effective strategy for attacking in terms of increasing shots at goal.

We examined effects of attentional focus on swimming speed. Participants' task was to swim one length of a pool (16 m) using the front crawl stroke. In Experiment 1, intermediate swimmers were given attentional focus instructions related to the crawl arm stroke or the leg kick, respectively. Participants were instructed to focus on “pulling your hands back” or “pushing the instep down” (internal focus), or on “pushing the water back/down” (external focus), respectively. Swim times were significantly shorter with an external focus. In Experiment 2, a control condition was included. Times were significantly faster in the external focus compared with both the internal focus and control conditions. These findings have implications for enhancing performance in swimming.

This study had as objective to investigate the effects of practice schedule on the adaptive process of motor learning. The experimental design consisted of four practice groups (constant, random, constant-random and random-constant), and two learning phases (stabilization and adaptation). In three experiments, children performed a complex task of coincident timing, in which the varied practice was manipulated in terms of visual stimulus (Experiment 1), movement pattern (Experiment 2), and a combination of both (Experiment 3). In Experiment 1, the constant, constant-random, and random-constant groups showed better performance in the adaptation phase than did the random group. In Experiment 2, the constant and constantrandom groups performed better than did the others. And, in Experiment 3, the constant-random group demonstrated better performance than the others. Overall results indicated that, during the adaptive process of motor skill acquisition, constant and constant-random practice, were superior to random and random-constant practice.