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Ecological dynamics of decision-making in the sport of sailing exemplifies emergent, conditionally coupled, co-adaptive behaviours. In this study, observation of the coupling dynamics of paired boats during competitive sailing showed that decision-making can be modelled as a self-sustained, co-adapting system of informationally coupled oscillators (boats). Bytracing the spatial-temporal displacements of the boats, time series analyses (autocorrelations, periodograms and running correlations) revealed that trajectories of match racing boats are coupled more than 88% of the time during a pre-start race, via continuous, competing co-adaptions between boats. Results showed that both the continuously selected trajectories of the sailors (12 years of age) and their categorical starting point locations were examples of emergent decisions. In this dynamical conception of decision-making behaviours, strategic positioning (categorical) and continuous displacement of a boat over the course in match-race sailing emerged as a function of interacting task, personal and environmental constraints. Results suggest how key interacting constraints could be manipulated in practice to enhance sailors' perceptual attunement to them in competition.

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Extant models of decision making in social neurobiological systems have typically explained task dynamics as characterized by transitions between two attractors. In this paper, we model a three-attractor task exemplified in a team sport context. The model showed that an attacker-defender dyadic system can be described by the angle x between a vector connecting the participants and the try line. This variable was proposed as an order parameter of the system and could be dynamically expressed by integrating a potential function. Empirical evidence has revealed that this kind of system has three stable attractors, with a potential function of the form V(x)=2k 1 x + k 2 ax 2 /22bx 4 /4 + x 6 /6, where k 1 and k 2 are two control parameters. Random fluctuations were also observed in system behavior, modeled as white noise e t , leading to the motion equation dx/dt = 2dV/dx + Q 0.5 e t , where Q is the noise variance. The model successfully mirrored the behavioral dynamics of agents in a social neurobiological system, exemplified by interactions of players in a team sport.

This study investigated interpersonal coordination tendencies in 1vs.1 dyads in rugby union, here expressed by participants' movement velocity towards or away from the sideline as they competed to score or prevent a try. We examined whether coupling tendencies of members of each dyad shaped key performance outcomes (try or successful tackle). Data on movement displacement trajectories of eight male rugby union players (aged 11-12 years) were analysed during performance in 47 trials. To assess coordination tendencies during exploratory behaviours in the dyads, analyses of performance time series data were undertaken using variable time graphs, running correlations and cross-correlations. Results revealed distinct coupling patterns characterised by shifts between synchronous coordination and asynchronous coordination tendencies and uncoordinated actions. Observed behaviours were interpreted as attempts of competing participants to create and perceive possibilities for action while seeking to achieve specific performance goals. Findings also revealed that a variety of patterned relations between participants resulted in different performance outcomes.

The goal of this study was to examine what experiences members have with fitness centers that influence their intentions for recommendation. After item generation and content validity, as well as a pilot test, a survey was conducted among members of five different clubs (n=1750). The questionnaire included measures of service quality attributes, accessibility, well-being in life, well-being in a club, and intentions to recommend a fitness center. Results using a structural equation model provide evidence that only service quality attributes and well-being in a club have positive effect on intentions of users to recommend it. Well-being in life has a negative effect on the intentions for recommendation, while accessibility shows no predictive effect. These findings suggest implications for the management of a club, such as the need to create a pleasant environment and to provide a personalized service directed towards the members' goals in order to improve well-being in a club and contribute to increase the intentions to recommend the fitness centers to others.Keywords: intentions to recommend, service quality attributes, accessibility, well-being Resumo-"Uma análise das intenções de usuários em recomedar serviços de centros de atividade fisica." O objetivo deste estudo foi examinar como as experiências de usuários de centros de atividade física interferem nas intenções em recomendar serviços. Depois de gerar itens e validar o conteúdo, aplicou-se um pré-teste, o questionário final foi aplicado a sócios de cinco clubes de fitness (n=1.750). O questionário incluiu atributos da qualidade do serviço, acessibilidade, bem-estar na vida, bem-estar no clube e intenção de recomendar. O modelo de equações estruturais mostrou que apenas os atributos da qualidade do serviço e bem-estar no clube têm um efeito positivo sobre as intenções de recomendar. O bem-estar na vida tem um efeito negativo sobre as intenções para recomendar, enquanto que a acessibilidade não mostra nenhum efeito preditivo. Estas conclusões sugerem a necessidade de criar um ambiente agradável nos clubes e de oferecer um serviço personalizado para os objetivos dos sócios, a fim de melhorar o bem-estar no clube e contribuir para a intenção de recomendar o ginásio.Palavras-chave: intenção de recomendar, atributos da qualidade do serviço, acessibilidade, bem-estar Resumen-"Un análisis a las intenciones de los socios para recomendar gimnasios." El objetivo de este estudio fue examinar los antecedentes de las intenciones de los socios para recomendar su gimnasio. Después de generar ítems y validar el contenido, se aplicó un pre-test, el cuestionario final fue aplicado a socios de cinco clubes de fitness (n=1.750). El cuestionario incluyó atributos de la cualidad del servicio, accesibilidad, bienestar en la vida, bienestar en el club e intención de recomendar. El modelo de ecuaciones estructurales mostró que solo los atributos de la cualidad del servicio y bienestar en el club tiene un efecto positivo sobre las intenciones de recomendar. El bienestar en la vida t...

This study analyzes the immediate effects of wearing a Therasuit on sagittal plane lower limb angular displacements during gait in children with unilateral spastic cerebral palsy (US-CP). Seven participants (median age = 7.00 years; ranging from 5.83 to 9.00 years) with US-CP, levels I and II of the Gross Motor Function Classification System, were assessed with kinematic gait analysis in three different conditions: (A) Baseline; (B) Therasuit without elastics and (C) Therasuit with elastics. Significant improvements were observed at the hip joint of both lower limbs during most of the gait cycle in participants wearing a Therasuit, including a decrease in the flexion pattern at the initial contact and swing phase in both lower limbs, and an increase in the extension pattern in the paretic lower limb during the stance phase. At the knee joint in the paretic lower limb, significant differences were found between the baseline and Therasuit with elastics conditions on the knee angle at initial contact, and between baseline and both Therasuit conditions on the flexion angle at swing phase. However, the inter-individual variability in kinematic patterns at the knee joint was high. At the ankle joint, decreased plantar flexion at initial contact and increased dorsiflexion during stance and swing phases were observed at the Therasuit with elastics condition, helping to correct the equinus-foot in the paretic lower limb during the whole gait cycle. The Z-values showed large effect sizes particularly for most of the angular hip variables in both lower limbs and for the angular ankle variables in the paretic lower limb. The Therasuit seems to have some positive immediate effects on gait kinematics in children with spastic unilateral cerebral palsy by providing a more functional and safer gait pattern. Future investigations with larger samples are recommended to further support these findings.

This paper analyzes effects of different practice task constraints on heart rate (HR) variability during 4v4 smallsided football games. Participants were sixteen football players divided into two age groups (U13, Mean age: 12.4±0.5 yrs; U15: 14.6±0.5). The task consisted of a 4v4 sub-phase without goalkeepers, on a 25x15 m field, of 15 minutes duration with an active recovery period of 6 minutes between each condition. We recorded players' heart rates using heart rate monitors (Polar Team System, Polar Electro, Kempele, Finland) as scoring mode was manipulated (line goal: scoring by dribbling past an extended line; double goal: scoring in either of two lateral goals; and central goal: scoring only in one goal). Subsequently, %HR reserve was calculated with the Karvonen formula. We performed a time-series analysis of HR for each individual in each condition. Mean data for intra-participant variability showed that autocorrelation function was associated with more short-range dependence processes in the "line goal" condition, compared to other conditions, demonstrating that the "line goal" constraint induced more randomness in HR response. Relative to inter-individual variability, line goal constraints demonstrated lower %CV and %RMSD (U13: 9% and 19%; U15: 10% and 19%) compared with double goal (U13: 12% and 21%; U15: 12% and 21%) and central goal (U13: 14% and 24%; U15: 13% and 24%) task constraints, respectively. Results suggested that line goal constraints imposed more randomness on cardiovascular stimulation of each individual and lower inter-individual variability than double goal and central goal constraints.