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This study compared decision-making (DM) of experienced and novice volleyball coaches while measuring blood flow brain activation with functional near-infrared spectroscopy. We sampled 34 coaches (mean [ M] age of 32.5, standard deviation [ SD] = 9.4 years) divided into two experience groups: (a) novice ( M = 2.8, SD = 1.9 years) and (b) experienced (M = 19, SD = 7.2 years). We evaluated coaches' DM through their responses to video-based scenarios of attacks performed in the extremities of the net within the Declarative Tactical Knowledge Test in Volleyball. We found no significant DM differences between the two groups of coaches ( p = .063), though novice (vs. experienced) coaches showed greater blood flow of the prefrontal cortex when visualizing the game situations. While experienced coaches may have better prefrontal neural efficiency during DM in these situations, further research is needed to evaluate other cerebral areas; since blood flow is an indirect measure of neural efficiency, and activity in remaining cortical components was unknown in this study.

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This study examined 142 volleyball games of the Men's Super League 2014/2015 seasons in Brazil from which we analyzed 24-26 games of each participating team, identifying 5,267 Zone 4 attacks for further analysis. Within these Zone 4 attacks, we analyzed the association between the effect of the attack carried out and the separate effects of serve reception, tempo and type of attack. We found that the reception, tempo of attack, second tempo of attack, and power of diagonal attack were predictors of the attack effect in Zone 4. Moreover, placed attacks showed a tendency to not yield a score. In conclusion, winning points in high-level men's volleyball requires excellent receptions, a fast attack tempo and powerfully executed of attacks.

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OBJECTIVE: To assess the influence of diabetic neuropathy (DN) on balance and functional strength in patients with diabetes mellitus type 2 (DM2). DESIGN: Cross-sectional study. SETTING: Diabetes outpatient unit. PARTICIPANTS: Adults (N=62; age range, 40-65y): 32 with DM2 (19 subjects without DN and 13 with DN) and 30 without DM2 (control group). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Upright balance, evaluated in 4 situations (fixed platform, unstable platform, with eyes open, with eyes closed), and functional strength, assessed with a five-times-sit-to-stand test, were analyzed using an electromagnetic system, with a sensor placed over C7 to allow maximum trunk displacements in the anterior-posterior and medial-lateral directions. The Berg Balance Scale and the Timed Up & Go test were also used. RESULTS: Subjects with DM2 had greater anterior-posterior displacement (P<.05) in the unstable platform with eyes closed condition compared with those without DM2, whereas no difference in medial-lateral displacement was observed between these groups. A difference in time was observed in the five-times-sit-to-stand test (P<.05), with subjects in the control group performing the tasks faster than either group of subjects with DM2. Additionally, subjects in the control group showed a higher score in the Berg Balance Scale and performed the Timed Up & Go test in less time compared with subjects in other groups. CONCLUSIONS: Subjects with DM2, with or without DN, showed deficits in postural control and functional strength compared with healthy individuals of the same age group.

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BACKGROUND: Walking speed seems to be related to aerobic capacity, lower limb strength, and functional mobility, however it is not clear whether there is a direct relationship between improvement in muscle strength and gait performance in early postmenopausal women. OBJECTIVE: To evaluate the effect of muscle strengthening exercises on the performance of the 6-minute walk test in women within 5 years of menopause. METHODS: The women were randomized into control group (n=31), which performed no exercise, and exercise group (n=27), which performed muscle strengthening exercises. The exercises were performed twice a week for 3 months. The exercise protocol consisted of warm-up, stretching, and strengthening of the quadriceps, hamstring, calf, tibialis anterior, gluteus maximus, and abdominal muscles, followed by relaxation. Muscular strength training started with 60% of 1MR (2 series of 10-15 repetitions), reaching 85% until the end of the 3-month period (4 series of 6 repetitions each). RESULTS: The between-group comparisons pre- and post-intervention did not show any difference in distance walked, heart rate or blood pressure (p>0.05), but showed differences in muscle strength post-intervention, with the exercise group showing greater strength (p CONCLUSION: The results suggest that muscle strengthening of the lower limbs did not improve performance in the 6-minute walk test in this population of postmenopausal women.

CONTEXTUALIZAÇÃO: A velocidade de marcha parece estar relacionada com a capacidade aeróbica, força dos músculos dos membros inferiores e mobilidade funcional. Entretanto, não está claro se existe uma relação direta entre a melhora da força muscular e o desempenho da marcha em mulheres pós-menopausais recentes. OBJETIVO: Avaliar o efeito de exercícios de fortalecimento muscular sobre o desempenho no teste de caminhada de 6 minutos em mulheres nos primeiros cinco anos após a menopausa. MÉTODOS: As mulheres foram randomizadas em grupo controle (n=31), que não realizou exercício, e grupo exercício (n=27), que realizou um programa de exercícios. O programa de exercícios foi realizado duas vezes por semana, durante três meses, e consistiu em aquecimento, alongamento, exercícios de fortalecimento muscular para quadríceps, isquiotibiais, tríceps sural, tibial anterior, glúteo máximo e abdominais, finalizando com relaxamento. O treinamento de força iniciou com 60% de 1RM (duas séries de 10-15 repetições) e atingiu 85% (quatro séries de seis repetições) no final dos três meses. RESULTADOS: As comparações entre os grupos pré e pós-três meses não mostraram diferenças para distância percorrida, frequência cardíaca (FC) e pressão arterial (p≥0,05), mas mostraram diferenças para força muscular após três meses, com o grupo exercício apresentando maior força (p≤0,05). Nas comparações antes e após três meses intragrupos, houve diferenças para FC, forças musculares de quadríceps e isquiotibiais para o grupo intervenção. CONCLUSÃO: Os resultados sugerem que o treinamento de força muscular dos membros inferiores não melhora o teste de caminhada de 6 minutos para essa população de mulheres avaliadas.

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BACKGROUND: Walking speed seems to be related to aerobic capacity, lower limb strength, and functional mobility, however it is not clear whether there is a direct relationship between improvement in muscle strength and gait performance in early postmenopausal women. OBJECTIVE: To evaluate the effect of muscle strengthening exercises on the performance of the 6-minute walk test in women within 5 years of menopause. METHODS: The women were randomized into control group (n=31), which performed no exercise, and exercise group (n=27), which performed muscle strengthening exercises. The exercises were performed twice a week for 3 months. The exercise protocol consisted of warm-up, stretching, and strengthening of the quadriceps, hamstring, calf, tibialis anterior, gluteus maximus, and abdominal muscles, followed by relaxation. Muscular strength training started with 60% of 1MR (2 series of 10-15 repetitions), reaching 85% until the end of the 3-month period (4 series of 6 repetitions each). RESULTS: The between-group comparisons pre- and post-intervention did not show any difference in distance walked, heart rate or blood pressure (p>0.05), but showed differences in muscle strength post-intervention, with the exercise group showing greater strength (p CONCLUSION: The results suggest that muscle strengthening of the lower limbs did not improve performance in the 6-minute walk test in this population of postmenopausal women.

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