Intelligence and academic achievement in a clinical adolescent population

Three canonical variate analyses were carried out on the CAT, WRAT, and WISC/WAIS scores obtained from a sample of 182 emotionally disturbed adolescents. A large general variate emerged in all three analyses. Two additional variates tentatively identified as attentional and symbolization factors also appeared in the analyses of the WRAT-WISC/WAIS and the WRAT-CAT.     

Variable-cam resistance training machines: do they match the angle - torque relationship in humans?

The aim of this study was to determine the extent to which the resistance provided by variable-cam resistance training machines match joint torque capability. Eight variable-cam knee extension machines from six different manufacturers were assessed. Resistive torque for a constant weight/load was measured at five knee joint angles. Knee extensor muscle torque capability--the angle-torque relationship--of 10 healthy young men was determined isometrically and dynamically at the same five angles. After normalization, the two relationships were compared. The angle - torque relationship of the knee extensors displayed an inverted "U" shape as expected, with dynamic torque changing by +40% on the ascending limb (1.75 - 1.40 rad) and -60% on the descending limb (1.05-0.35 rad) of the angle - torque relationship. The angle-torque relationship of the different training machines was highly variable, but consistently less curvilinear and significantly different from knee extensor capabilities, with changes in torque of +2.5 to +22.2% (ascending limb) and +37.6 to -20.5% (descending limb). It is recommended that variable-cam resistance training machines be designed with the angle - torque relationship of the relevant joint and the inertial profile of the lifting exercise in mind.     

如何成为思考型教练员

为扮演好各种角色,不同级别的教练员都必须掌握和使用越来越复杂的专业化知识。因此,世界上许多国家都提供大型的综合项目,来帮助教练员实现这一目标,教练员教育得到迅猛发展,教练员教育国际委员会应运而生。然而,在教练员看来,与正式的教育相比,他们在训练指导实践中所获得的知识更有利于其职业发展。研究显示,美国高校的教练员用于教练员培训机构的平均时间为每年25h,     

The effect of playing status,maturity status,and playing position on the development of match skills in elite youth football players aged 11–18 years: A mixed-longitudinal study

This mixed-longitudinal study examined the development of match skills in elite male youth footballers (aged 11–18 years), while considering the effect of playing status, maturity status, and playing position. Across two seasons, 126 elite male youth footballers were assessed in 1–10 competitive matches (401 player-matches). For each match, the on-the-ball actions of each player were recorded using a notation system. The match skills observed were frequencies of successful passes, on-target shots, dribbles, crosses, clearances, and tackles/blocks/interceptions. Multilevel Poisson analysis was used to model the development of players, with regard to each match skill. Modelling revealed significant (p?p?p?p?p?相似文献