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According to the neural efficiency hypothesis (NEH), individuals with higher expertise in a domain use their brain more efficiently when processing domain-specific tasks and show more efficient brain activity than individuals with lower expertise. In this study 64 participants with differing levels of volleyball expertise were recruited to investigate the NEH by means of a volleyball-specific tactical decision-making task. The participants, which were allocated to three different expertise groups (based on prior volleyball experience), saw videos of setting situations of real volleyball matches and were asked to predict the outcome of these situations. Behavioral performance and event-related de-/synchronization (ERD/S) in the EEG theta and alpha bands during the completion of the task, were examined. Our results show significantly higher prediction accuracy in relation to volleyball expertise. Significantly stronger theta synchronization, as well as alpha desynchronization were observed during the tactical prediction condition compared to a control condition. No significant group differences in theta or alpha ERD/S were observed. Descriptive examinations of theta and alpha ERD/S distributions, which revealed mixed results regarding support for the NEH, are discussed. Our findings provide new insights to the ongoing debate on how the NEH applies to the domain of sport. [ABSTRACT FROM AUTHOR]

To overcome a possible drop in performance following longer stretch durations (>60 s), post-stretching dynamic activities (PSA) can be applied. However, it is not clear if this is true for isolated proprioceptive neuromuscular facilitation (PNF) stretching of different muscle groups (e.g., triceps surae and quadriceps). Thus, 16 participants performed both interventions (triceps surae PNF + PSA; quadriceps PNF + PSA) in random order, separated by 48 h. Jump performance was assessed with a force plate, and tissue stiffness was assessed with a MyotonPro device. While no changes were detected in the countermovement jump performance, the PNF + PSA interventions resulted in a decrease in drop jump performance which led to a large magnitude of change following the triceps surae PNF + PSA and a small-to-medium magnitude of change following the quadriceps PNF + PSA. Moreover, in the triceps surae PNF + PSA intervention, a decrease in Achilles tendon stiffness was seen, while in the quadriceps PNF + PSA intervention, a decrease in the overall quadriceps muscle stiffness was seen. According to our results, we recommend that especially triceps surae stretching is avoided during warm-up (also when PSA is included) when the goal is to optimise explosive or reactive muscle contractions. [ABSTRACT FROM AUTHOR]

Physical activity has not only been associated with increased physical and mental health, but also with beneficial effects on various cognitive and brain functions. This study investigated the effects of a motor and coordination oriented exercise intervention on academic achievements, attention/concentration ability, and on different facets of creative potential in a sample of school-aged children between 11 and 14 years. The intervention was conducted during the morning school-break over a time period of 4 weeks (5 units per week). The intervention was associated with beneficial effects on attention/concentration ability, basic arithmetic competence, and the fluency facet of creative potential. The finding that regular physical exercise during the morning break improves some basic academic and cognitive functions may motivate efforts to implement physical activity programs as promising and effective tools in the everyday school-routine of the children to stimulate basic neurocognitive functions.

Purpose: Reported relationships between electromyographic (EMG) thresholds and systemic thresholds based on lactate, ventilation, or heart rate are contradictory. This might be related to the complexity of the investigated whole-body movements involving many muscles with different activation patterns. Therefore, the aim of the study was to investigate these relationships during an incremental single-joint exercise. Methods: Eighteen male subjects (29.7 [4.4] y) performed single-arm elbow flexions on a biceps curl machine with loads increasing every minute until exhaustion. EMG signals of the main elbow flexors (short and long head of the biceps brachii, flexor carpi radialis, and brachioradialis) as well as gas exchange variables, blood lactate concentration, and heart rate were measured, and 2 turn points based on a 3-phase model of metabolism were determined for each variable. Results: The first and second turn points for EMG were determined at 32.0% to 33.1% and 64.4% to 66.5% of maximal achieved performance (maximum weight), respectively. Systemic turn points were determined at 33.3% to 34.4% and 65.9% to 66.7% of maximum weight and were not significantly different from EMG turn points. Furthermore, systemic and EMG turn points showed a strong or very strong relationship at the first (ρ =.54–.93, P <.05) and second turn point (ρ =.76–.93, P <.01). Conclusions: A close relationship between EMG and systemic turn points could be confirmed for the applied movement of a small muscle group. The determination of local single muscle thresholds using EMG provides additional muscle-specific information about performance-limiting properties of muscles involved in endurance-type incremental exercise. [ABSTRACT FROM AUTHOR]

This study analysed self-reported musculoskeletal symptoms and training characteristics of high-performance Brazilian beach handball athletes. In a cross-sectional study, 28 men (mean (standard deviation), age: 23 (5) years, body mass: 81.9 (14.4) kg, height: 181.3 (8.6) cm, experience: 13.3 (5.4) years) and 27 women (mean (standard deviation), age: 28 (8) years, body mass: 65.5 (12.7) kg, height: 170.4 (4.9) cm, experience: 9.3 (3.0) years) answered an online questionnaire about anthropometric and sociodemographic aspects, musculoskeletal symptoms, and training characteristics. The results showed that the musculoskeletal symptoms are more prevalent in the knees during the previous seven days and in the shoulder during the previous 12 months. Left-wing players were more affected by musculoskeletal symptoms in the shoulder than right-wing players and central defenders during the previous seven days regardless of the sex. Problems in the elbow area presented a higher prevalence in the male players compared to the female players in the past 12-month period. The training volume was higher for men compared to women, regardless of the playing position. Moreover, beach handball athletes who reported training five days/week or 360 min/week or more were more likely to develop musculoskeletal symptoms in the elbow compared to those who had a lower frequency and duration of training. Musculoskeletal symptoms occurred most in the shoulders and knees, differing between sex and playing positions. Higher frequency and duration of training were independent risk factors for chronic musculoskeletal symptoms in the elbow compared to a lower volume of training. [ABSTRACT FROM AUTHOR]