Publications of articles with physical literacy as a topic have increased dramatically since the beginning of 2000 s. The aim of this paper is to,through an explorative literature overview with an inductive approach, ...Publications of articles with physical literacy as a topic have increased dramatically since the beginning of 2000 s. The aim of this paper is to,through an explorative literature overview with an inductive approach, analyze frequent, and significant themes in published peer reviewed articles,with a focus on physical literacy. The database EBSCO has been used with the identifiers “physical literacy” and “physical literacy and evidence”.Furthermore ICSSPE Bulletin＇s special issue on physical literacy has been included in the overview. The findings have resulted in three key themes： assumptions of the concept physical literacy and its educative role, sports development and physical literacy, and assessment and physical literacy. Future studies are needed to examine if the advocated pedagogical strategies based on the concept physical literacy have led to a reorganized and revitalized school subject. There is also an existing critique towards making physical literacy an idealistic neutral concept or synonym with fundamental movement skills or sports talent identification. The role of higher education emerges as crucial for the next step of the development of the scientific framework as this involves how physical literacy will be socially configured, nurtured, and embodied in practice.Copyright ó 2015, Shanghai University of Sport. Production and hosting by Elsevier B.V. All rights reserved.展开更多
Initially it was believed that phosphorylase was responsible for both glycogen breakdown and synthesis in the living cell.The discovery of glycogen synthase and McArdle's disease(lack of phosphorylase activity),to...Initially it was believed that phosphorylase was responsible for both glycogen breakdown and synthesis in the living cell.The discovery of glycogen synthase and McArdle's disease(lack of phosphorylase activity),together with the high Pi/glucose 1-P ratio in skeletal muscle,demonstrated that glycogen synthesis could not be attributed to reversal of the phosphorylase reaction.Rather,glycogen synthesis was attributable solely to the activity of glycogen synthase,subsequent to the transport of glucose into the cell.However,the well-established observation that phosphorylase was inactivated(i.e.,dephosphorylated)during the initial recovery period after prior exercise,when the rate of glycogen accumulation is highest and independent of insulin,suggested that phosphorylase could play an active role in glycogen accumulation.But the quantitative contribution of phosphorylase inactivation was not established until recently,when studying isolated murine muscle preparations during recovery from repeated contractions at temperatures ranging from 25 to 35C.Thus,in both slow-twitch,oxidative and fast-twitch,glycolytic muscles,inactivation of phosphorylase accounted for 45%–75%of glycogen accumulation during the initial hours of recovery following repeated contractions.Such data indicate that phosphorylase inactivation may be the most important mechanism for glycogen accumulation under defined conditions.These results support the initial belief that phosphorylase plays a quantitative role in glycogen formation in the living cell.However,the mechanism is not via activation of phosphorylase,but rather via inactivation of the enzyme.展开更多
Purpose To biomechanically profile force generation connected to the complex role of the trunk in double poling in a rep-resentative sample of Para-Nordic sit-skiers.Methods Twelve male World Cup Para-Nordic sit-skier...Purpose To biomechanically profile force generation connected to the complex role of the trunk in double poling in a rep-resentative sample of Para-Nordic sit-skiers.Methods Twelve male World Cup Para-Nordic sit-skiers(sport classes:LW10-12)were skiing on flat snow terrain at submaximal speed of 4.5 m/s(~73% max imum speed).2D video(50 Hz)and pole force analyses(1000 Hz)were performed synchronously,examining angle,force and cycle characteristics to analyse the role of the trunk in generating propulsion.Results LW10-11.5 skiers lost between 21%and 4%propulsive force versus LW12 athletes only due to different geomet-rics of the trunk and pole angle at an equal axial pole force.While LW10-11 skiers indicated trunk extension or position maintenance during pole thrust,LW11.5-12 skiers showed strong trunk flexion combined with smaller pole angles to the ground.Hence,LW11.5-12 skiers could create larger propulsive forces and therefore greater cycle lengths at lower cycle rates at the same speed.Maximum speed increased from LW10 to LW12 and was significantly correlated to trunk flexion range of motion(r=0.63)and cycle length(r=0.59).Trunk flexion ROM showed a significant relationship to the impulse of propulsive force(r=0.63)and pole angle to the ground(r=−0.76)(all P<0.05).Conclusion The impact of impairment on the force production profiles and its physiological-biomechanical consequences need further investigation also in other terrains and at wider spectrums of skiing speeds.The evident problem of low numbers of LW10-11 skiers in World Cup needs creative future solutions for research.展开更多
文摘Publications of articles with physical literacy as a topic have increased dramatically since the beginning of 2000 s. The aim of this paper is to,through an explorative literature overview with an inductive approach, analyze frequent, and significant themes in published peer reviewed articles,with a focus on physical literacy. The database EBSCO has been used with the identifiers “physical literacy” and “physical literacy and evidence”.Furthermore ICSSPE Bulletin＇s special issue on physical literacy has been included in the overview. The findings have resulted in three key themes： assumptions of the concept physical literacy and its educative role, sports development and physical literacy, and assessment and physical literacy. Future studies are needed to examine if the advocated pedagogical strategies based on the concept physical literacy have led to a reorganized and revitalized school subject. There is also an existing critique towards making physical literacy an idealistic neutral concept or synonym with fundamental movement skills or sports talent identification. The role of higher education emerges as crucial for the next step of the development of the scientific framework as this involves how physical literacy will be socially configured, nurtured, and embodied in practice.Copyright ó 2015, Shanghai University of Sport. Production and hosting by Elsevier B.V. All rights reserved.
文摘Initially it was believed that phosphorylase was responsible for both glycogen breakdown and synthesis in the living cell.The discovery of glycogen synthase and McArdle's disease(lack of phosphorylase activity),together with the high Pi/glucose 1-P ratio in skeletal muscle,demonstrated that glycogen synthesis could not be attributed to reversal of the phosphorylase reaction.Rather,glycogen synthesis was attributable solely to the activity of glycogen synthase,subsequent to the transport of glucose into the cell.However,the well-established observation that phosphorylase was inactivated(i.e.,dephosphorylated)during the initial recovery period after prior exercise,when the rate of glycogen accumulation is highest and independent of insulin,suggested that phosphorylase could play an active role in glycogen accumulation.But the quantitative contribution of phosphorylase inactivation was not established until recently,when studying isolated murine muscle preparations during recovery from repeated contractions at temperatures ranging from 25 to 35C.Thus,in both slow-twitch,oxidative and fast-twitch,glycolytic muscles,inactivation of phosphorylase accounted for 45%–75%of glycogen accumulation during the initial hours of recovery following repeated contractions.Such data indicate that phosphorylase inactivation may be the most important mechanism for glycogen accumulation under defined conditions.These results support the initial belief that phosphorylase plays a quantitative role in glycogen formation in the living cell.However,the mechanism is not via activation of phosphorylase,but rather via inactivation of the enzyme.
文摘Purpose To biomechanically profile force generation connected to the complex role of the trunk in double poling in a rep-resentative sample of Para-Nordic sit-skiers.Methods Twelve male World Cup Para-Nordic sit-skiers(sport classes:LW10-12)were skiing on flat snow terrain at submaximal speed of 4.5 m/s(~73% max imum speed).2D video(50 Hz)and pole force analyses(1000 Hz)were performed synchronously,examining angle,force and cycle characteristics to analyse the role of the trunk in generating propulsion.Results LW10-11.5 skiers lost between 21%and 4%propulsive force versus LW12 athletes only due to different geomet-rics of the trunk and pole angle at an equal axial pole force.While LW10-11 skiers indicated trunk extension or position maintenance during pole thrust,LW11.5-12 skiers showed strong trunk flexion combined with smaller pole angles to the ground.Hence,LW11.5-12 skiers could create larger propulsive forces and therefore greater cycle lengths at lower cycle rates at the same speed.Maximum speed increased from LW10 to LW12 and was significantly correlated to trunk flexion range of motion(r=0.63)and cycle length(r=0.59).Trunk flexion ROM showed a significant relationship to the impulse of propulsive force(r=0.63)and pole angle to the ground(r=−0.76)(all P<0.05).Conclusion The impact of impairment on the force production profiles and its physiological-biomechanical consequences need further investigation also in other terrains and at wider spectrums of skiing speeds.The evident problem of low numbers of LW10-11 skiers in World Cup needs creative future solutions for research.
