"Plyometrics"练习是一种把退让练习和克制练习结合在一起的训练方法,对提高运动员爆发力有着重要的作用,对运动员的基础力量也有要求。WCBA教练员对运动员的力量要求偏低;WCBA运动员无论是上肢的卧推,还是下肢的深蹲都不能达..."Plyometrics"练习是一种把退让练习和克制练习结合在一起的训练方法,对提高运动员爆发力有着重要的作用,对运动员的基础力量也有要求。WCBA教练员对运动员的力量要求偏低;WCBA运动员无论是上肢的卧推,还是下肢的深蹲都不能达到"Plyometrics"练习理论上的要求。在此力量的基础上,WCBA运动员应较多地进行"Upper Body Plyometrics"练习,有利于运动员爆发力和灵敏性的提高。对有下肢肌腱劳损的WCBA运动员,也可进行"Upper Body Plyometrics"练习,提高其爆发力。展开更多
现有知识追踪模型大多以概念为中心评估学生的未来表现,忽略了包含相同概念的练习之间的差异,从而影响模型的预测准确性。此外,在构建学生知识状态过程中,现有模型未能充分利用学生在答题过程中的学习遗忘特征,导致对学生知识状态的刻...现有知识追踪模型大多以概念为中心评估学生的未来表现,忽略了包含相同概念的练习之间的差异,从而影响模型的预测准确性。此外,在构建学生知识状态过程中,现有模型未能充分利用学生在答题过程中的学习遗忘特征,导致对学生知识状态的刻画不够精确。针对以上问题,提出了一种练习嵌入和学习遗忘特征增强的知识追踪模型(exercise embeddings and learning-forgetting features boosted knowledge tracing, ELFBKT)。该模型利用练习概念二部图中的显性关系,深入计算二部图中的隐性关系,构建了一个练习概念异构关系图。为充分利用异构图中的丰富关系信息,ELFBKT模型引入了关系图卷积网络。通过该网络的处理,模型能够增强练习嵌入的质量,并以练习为中心更准确地预测学生的未来表现。此外,ELFBKT充分利用多种学习遗忘特征,构建了两个门控机制,分别针对学生的学习行为和遗忘行为进行建模,更精确地刻画学生的知识状态。在两个真实世界数据集上进行实验,结果表明ELFBKT在知识追踪任务上的性能优于其他模型。展开更多
Purpose:This study aimed to assess the effectiveness and time course for improvements in explosive actions through resistance training(RT)vs.plyometric training(PT)in prepubertal soccer players.Methods:Thirty-four mal...Purpose:This study aimed to assess the effectiveness and time course for improvements in explosive actions through resistance training(RT)vs.plyometric training(PT)in prepubertal soccer players.Methods:Thirty-four male subjects were assigned to:a control group(n=11);an RT group(5 regular soccer training sessions per week,n=12);a PT group(3 soccer training sessions and 2 RT sessions per week,n=11).The outcome measures included tests for the assessment of muscle strength(e.g.,1 repetition maximum half-squat test),jump ability(e.g.,countermovement jump,squat jump,standing long jump,and multiple 5 bounds test),linear speed(e.g.,20m sprint test),and change of direction(e.g.,Illinois change of direction test).Results:The RTG showed an improvement in the half-squat(△=13.2%;d=1.3,p<0.001)and countermovement jump(△=9.4%;d=2.4,p<0.001)at Week 4,whereas improvements in the 20-m sprint(△=4.2%;d=1.1,p<0.01);change of direction(CoD)(△=3.8%;d=2.1,p<0.01);multiple 5 bounds(△=5.1%;d=1.5,p<0.05);standing long jump(△=7.2%;d=1.2,p<0.01);squat jump(△=19.6%;d=1.5,p<0.01);were evident at Week 8.The PTG showed improvements in CoD(△=2.1%;d=1.3,p<0.05);standing long jump(△=9.3%;d=1.1,p<0.01);countermovement jump(△=16.1%;d=1.2,p<0.01);and squat jump(△=16.7%;d=1.4,p<0.01);at Week 8 whereas improvements in the 20-m sprint(△=4.1%;d=1.3,p<0.01);and multiple 5 bounds(△=7.4%;d=2.4,p<0.001);were evident only after Week.The RT and PT groups showed improvements in all sprint,CoD,and jump tests(p<0.05)and in half-squat performance,for which improvement was only shown within the RTG(p<0.001).Conclusion:RT and PT conducted in combination with regular soccer training are safe and feasible interventions for prepubertal soccer players.In addition,these interventions were shown to be effective training tools to improve explosive actions with different time courses of improvements,which manifested earlier in the RTG than in the PTG.These outcomes may help coaches and fitness trainers set out clear and concise goals of training according to the specific time course of improvement difference between RT and PT on proxies of athletic performance of prepubertal soccer players.展开更多
文摘"Plyometrics"练习是一种把退让练习和克制练习结合在一起的训练方法,对提高运动员爆发力有着重要的作用,对运动员的基础力量也有要求。WCBA教练员对运动员的力量要求偏低;WCBA运动员无论是上肢的卧推,还是下肢的深蹲都不能达到"Plyometrics"练习理论上的要求。在此力量的基础上,WCBA运动员应较多地进行"Upper Body Plyometrics"练习,有利于运动员爆发力和灵敏性的提高。对有下肢肌腱劳损的WCBA运动员,也可进行"Upper Body Plyometrics"练习,提高其爆发力。
文摘现有知识追踪模型大多以概念为中心评估学生的未来表现,忽略了包含相同概念的练习之间的差异,从而影响模型的预测准确性。此外,在构建学生知识状态过程中,现有模型未能充分利用学生在答题过程中的学习遗忘特征,导致对学生知识状态的刻画不够精确。针对以上问题,提出了一种练习嵌入和学习遗忘特征增强的知识追踪模型(exercise embeddings and learning-forgetting features boosted knowledge tracing, ELFBKT)。该模型利用练习概念二部图中的显性关系,深入计算二部图中的隐性关系,构建了一个练习概念异构关系图。为充分利用异构图中的丰富关系信息,ELFBKT模型引入了关系图卷积网络。通过该网络的处理,模型能够增强练习嵌入的质量,并以练习为中心更准确地预测学生的未来表现。此外,ELFBKT充分利用多种学习遗忘特征,构建了两个门控机制,分别针对学生的学习行为和遗忘行为进行建模,更精确地刻画学生的知识状态。在两个真实世界数据集上进行实验,结果表明ELFBKT在知识追踪任务上的性能优于其他模型。
文摘Purpose:This study aimed to assess the effectiveness and time course for improvements in explosive actions through resistance training(RT)vs.plyometric training(PT)in prepubertal soccer players.Methods:Thirty-four male subjects were assigned to:a control group(n=11);an RT group(5 regular soccer training sessions per week,n=12);a PT group(3 soccer training sessions and 2 RT sessions per week,n=11).The outcome measures included tests for the assessment of muscle strength(e.g.,1 repetition maximum half-squat test),jump ability(e.g.,countermovement jump,squat jump,standing long jump,and multiple 5 bounds test),linear speed(e.g.,20m sprint test),and change of direction(e.g.,Illinois change of direction test).Results:The RTG showed an improvement in the half-squat(△=13.2%;d=1.3,p<0.001)and countermovement jump(△=9.4%;d=2.4,p<0.001)at Week 4,whereas improvements in the 20-m sprint(△=4.2%;d=1.1,p<0.01);change of direction(CoD)(△=3.8%;d=2.1,p<0.01);multiple 5 bounds(△=5.1%;d=1.5,p<0.05);standing long jump(△=7.2%;d=1.2,p<0.01);squat jump(△=19.6%;d=1.5,p<0.01);were evident at Week 8.The PTG showed improvements in CoD(△=2.1%;d=1.3,p<0.05);standing long jump(△=9.3%;d=1.1,p<0.01);countermovement jump(△=16.1%;d=1.2,p<0.01);and squat jump(△=16.7%;d=1.4,p<0.01);at Week 8 whereas improvements in the 20-m sprint(△=4.1%;d=1.3,p<0.01);and multiple 5 bounds(△=7.4%;d=2.4,p<0.001);were evident only after Week.The RT and PT groups showed improvements in all sprint,CoD,and jump tests(p<0.05)and in half-squat performance,for which improvement was only shown within the RTG(p<0.001).Conclusion:RT and PT conducted in combination with regular soccer training are safe and feasible interventions for prepubertal soccer players.In addition,these interventions were shown to be effective training tools to improve explosive actions with different time courses of improvements,which manifested earlier in the RTG than in the PTG.These outcomes may help coaches and fitness trainers set out clear and concise goals of training according to the specific time course of improvement difference between RT and PT on proxies of athletic performance of prepubertal soccer players.
