Purpose: The aims of this study were to:(1) provide a comprehensive physiological profile of simulated basketball activity and(2) identify temporal changes in player responses in controlled settings.Methods: State-lev...Purpose: The aims of this study were to:(1) provide a comprehensive physiological profile of simulated basketball activity and(2) identify temporal changes in player responses in controlled settings.Methods: State-level male basketball players(n = 10) completed 4 × 10 min simulated quarters of basketball activity using a reliable and valid courtbased test. A range of physiological(ratings of perceived exertion, blood lactate concentration([BLa~—]), blood glucose concentration([BGlu]), heart rate(HR), and hydration) and physical(performance and fatigue indicators for sprint, circuit, and jump activity) measures were collected across testing.Results: Significantly reduced [BLa~—](6.19 ± 2.30 vs. 4.57 ± 2.33 mmol/L; p = 0.016) and [BGlu](6.91 ± 1.57 vs. 5.25 ± 0.81 mmol/L;p = 0.009) were evident in the second half. A mean HR of 180.1 ± 5.7 beats/min(90.8% ± 4.0% HR max) was observed, with a significant increase in vigorous activity(77%—95% HR max)(11.31 ± 6.91 vs. 13.50 ± 6.75 min; p = 0.024) and moderate decrease in near-maximal activity(>95% HR_(max))(7.24 ± 7.45 vs. 5.01 ± 7.20 min) in the second half. Small increases in performance times accompanied by a significantly lower circuit decrement(11.67% ± 5.55% vs. 7.30% ± 2.16%; p = 0.032) were apparent in the second half.Conclusion: These data indicate basketball activity imposes higher physiological demands than previously thought and temporal changes in responses might be due to adapted pacing strategies as well as fatigue-mediated mechanisms.展开更多
This paper devotes to rational design for the ship propellers with long wavy blades. Thin long blades create big elastic deformations, which can be a regulator of an optimum angle for attack. The wavy form provides st...This paper devotes to rational design for the ship propellers with long wavy blades. Thin long blades create big elastic deformations, which can be a regulator of an optimum angle for attack. The wavy form provides stability on operational modes. To ensure stabilization to decrease in bending and torsion fluctuations, the main sectorial coordinates were defined by combining the shift centre with the gravity centre for computer geometrical models of the rowing screw blade and an idealized elastic deformable boundary liquid flow layer while unit thickness was offered. More rational petal forms of the long blade with a wavy surface are explained for exception of not free torsion.展开更多
Using proper footwear is crucial to avoid pain, deformations and injuries on foot. For athletes, a pair of good shoes is vital for comfort and may add to performance improvement. The main objective of this study is to...Using proper footwear is crucial to avoid pain, deformations and injuries on foot. For athletes, a pair of good shoes is vital for comfort and may add to performance improvement. The main objective of this study is to study the performance of some commonly used shoes in the takraw games by using experimental tests and thermal measurements. The momentum and kinetic energies that were generated by the takraw shoes were also measured. The methods used in this study included free fall test, impact force analysis and surface thermal assessment. From the outcomes of the experiments, it was found that the prototype FA shoe was better in absorption of momentum and impact force than the other shoes and also with lower surface temperature after the trial game. These outcomes suggested that it was more suitable to be worn by the takraw players for better performance. All the information obtained from this study are particularly useful for improvement on the current design oftakraw shoe.展开更多
Sports competition is competition in a particular environment, mad it has its own characteristics, tasks, opponents, environment and methods. Despite the psychological training is relevant to, and associated with phys...Sports competition is competition in a particular environment, mad it has its own characteristics, tasks, opponents, environment and methods. Despite the psychological training is relevant to, and associated with physical exercise, but its nature determines its specificity. On the psychological point of view, due to the reinforcement of external stimuli, which led to strong psychological pressure, these are manifested through the behaviors of the players when they are compete with others, such as fear, excessive psychological tension, incorrect competition motivation, ambiguous purpose, lack of confidence, even there are phenomenon like isolated characteristics and irritation, etc. Thus, the regulation and control of mental activity, the overcome of the psychological barriers, and the implementation of the psychology training have become a big question which teachers and coaches must pay attention to and need to be solved.展开更多
基金support of the players and coaches in the Rockhampton representative U18 team
文摘Purpose: The aims of this study were to:(1) provide a comprehensive physiological profile of simulated basketball activity and(2) identify temporal changes in player responses in controlled settings.Methods: State-level male basketball players(n = 10) completed 4 × 10 min simulated quarters of basketball activity using a reliable and valid courtbased test. A range of physiological(ratings of perceived exertion, blood lactate concentration([BLa~—]), blood glucose concentration([BGlu]), heart rate(HR), and hydration) and physical(performance and fatigue indicators for sprint, circuit, and jump activity) measures were collected across testing.Results: Significantly reduced [BLa~—](6.19 ± 2.30 vs. 4.57 ± 2.33 mmol/L; p = 0.016) and [BGlu](6.91 ± 1.57 vs. 5.25 ± 0.81 mmol/L;p = 0.009) were evident in the second half. A mean HR of 180.1 ± 5.7 beats/min(90.8% ± 4.0% HR max) was observed, with a significant increase in vigorous activity(77%—95% HR max)(11.31 ± 6.91 vs. 13.50 ± 6.75 min; p = 0.024) and moderate decrease in near-maximal activity(>95% HR_(max))(7.24 ± 7.45 vs. 5.01 ± 7.20 min) in the second half. Small increases in performance times accompanied by a significantly lower circuit decrement(11.67% ± 5.55% vs. 7.30% ± 2.16%; p = 0.032) were apparent in the second half.Conclusion: These data indicate basketball activity imposes higher physiological demands than previously thought and temporal changes in responses might be due to adapted pacing strategies as well as fatigue-mediated mechanisms.
文摘This paper devotes to rational design for the ship propellers with long wavy blades. Thin long blades create big elastic deformations, which can be a regulator of an optimum angle for attack. The wavy form provides stability on operational modes. To ensure stabilization to decrease in bending and torsion fluctuations, the main sectorial coordinates were defined by combining the shift centre with the gravity centre for computer geometrical models of the rowing screw blade and an idealized elastic deformable boundary liquid flow layer while unit thickness was offered. More rational petal forms of the long blade with a wavy surface are explained for exception of not free torsion.
文摘Using proper footwear is crucial to avoid pain, deformations and injuries on foot. For athletes, a pair of good shoes is vital for comfort and may add to performance improvement. The main objective of this study is to study the performance of some commonly used shoes in the takraw games by using experimental tests and thermal measurements. The momentum and kinetic energies that were generated by the takraw shoes were also measured. The methods used in this study included free fall test, impact force analysis and surface thermal assessment. From the outcomes of the experiments, it was found that the prototype FA shoe was better in absorption of momentum and impact force than the other shoes and also with lower surface temperature after the trial game. These outcomes suggested that it was more suitable to be worn by the takraw players for better performance. All the information obtained from this study are particularly useful for improvement on the current design oftakraw shoe.
文摘Sports competition is competition in a particular environment, mad it has its own characteristics, tasks, opponents, environment and methods. Despite the psychological training is relevant to, and associated with physical exercise, but its nature determines its specificity. On the psychological point of view, due to the reinforcement of external stimuli, which led to strong psychological pressure, these are manifested through the behaviors of the players when they are compete with others, such as fear, excessive psychological tension, incorrect competition motivation, ambiguous purpose, lack of confidence, even there are phenomenon like isolated characteristics and irritation, etc. Thus, the regulation and control of mental activity, the overcome of the psychological barriers, and the implementation of the psychology training have become a big question which teachers and coaches must pay attention to and need to be solved.
