Background: Although the standing long jump (SLJ) is a popular physical fitness assessment, it lacks an updated criterion-reference standard. This study generated the first normative SLJ test data for Chinese aged 8 -...Background: Although the standing long jump (SLJ) is a popular physical fitness assessment, it lacks an updated criterion-reference standard. This study generated the first normative SLJ test data for Chinese aged 8 - 18. Methods: From September 2005 to December 2011, comprehensive physical fitness assessments were conducted on 12,712 school students. The SLJ performances were significantly different between boys and girls (all age groups, p < 0.01). Results: The boys performed better than the girls in each age group. The mean difference increased as the age increased, depicting a prominent variance in muscular strength between boys and girls at age 12, and the variances became larger at age 18. Girls in the 70th percenttile performed similarly to boys performing in the 10th percentile. The onset of muscle strength for boys found in this study corresponded to the onset age of testosterone maturation of Chinese boys investigated in previous studies. Linear regression found age and BMI predicting SLJ significantly for boys and girls, explaining better SLJ results in older boy and the effect of their heavy body size. Conclusions: This study indicated a muscular strength difference between genders during growth and added supporting evidence to the hormonal influence of muscle growth during puberty.展开更多
Background: This is the first study to publish the normative reference values for assessment of the level of muscular strength through the “standing long jump” test carried out on a large sample of Macedonian school...Background: This is the first study to publish the normative reference values for assessment of the level of muscular strength through the “standing long jump” test carried out on a large sample of Macedonian school children. The normative values encompass a wide span of years (6 - 18). Methods: The research was realized in a large sample of 12618 school children at the age of 6 to 18 years from Macedonia. The sample was divided in 14 groups, according to chronological age and each age group was divided into two subgroups according to the criteria of gender. For estimation of the morphologic characteristics, the following anthropometric measures have been applied: body height in standing position (cm), body weight (kg), as well as the body mass index (BMI). Children aged 6 or above were invited to take a standing long jump test. Results: Boys show statistically better results in all age categories in the standing long jump test than girls, and these differences become bigger with the increase of age, especially after the 14th year展开更多
In this paper we consider the problem of testing long memory for a continuous time process based on high frequency data. We provide two test statistics to distinguish between a semimartingale and a fractional integral...In this paper we consider the problem of testing long memory for a continuous time process based on high frequency data. We provide two test statistics to distinguish between a semimartingale and a fractional integral process with jumps, where the integral is driven by a fractional Brownian motion with long memory. The small-sample performances of the statistics are evidenced by means of simulation studies. The real data analysis shows that the fractional integral process with jumps can capture the long memory of some financial data.展开更多
目的:以立定跳远动作为例,检验不同注意焦点对学龄前儿童立定跳远结果指标距离和过程指标动作得分的影响,并从运动学角度分析注意焦点影响立定跳远练习效果的潜在机制,探究注意焦点在学龄前儿童基本动作技能教学中的作用。方法:选取46名...目的:以立定跳远动作为例,检验不同注意焦点对学龄前儿童立定跳远结果指标距离和过程指标动作得分的影响,并从运动学角度分析注意焦点影响立定跳远练习效果的潜在机制,探究注意焦点在学龄前儿童基本动作技能教学中的作用。方法:选取46名4.5~6.0岁的学龄前儿童为受试者,采用受试者内平衡的研究设计分别测试这些儿童在内部、外部和无特定注意焦点指令引导下的立定跳远动作,并分别应用Qualisys红外高速运动捕捉系统和Sony摄像机采集学龄前儿童立定跳远的运动学数据和动作视频。结果:1)与对照组和内部注意焦点组相比,外部注意焦点组的立定跳远距离显著增加(97.7 cm vs 98.9 cm vs104.2 cm,F=23.544,P<0.05),但立定跳远动作得分在各组间无显著性差异(F=0.764,P=0.392)。2)与对照组和内部注意焦点组相比,在预蹲阶段,外部注意焦点组的髋关节(77.2°vs73.9°vs 61.5°,F=49.320,P<0.05)和膝关节角度(110.4°vs 113.7°vs 102.6°,F=31.803,P<0.05)显著减小;在蹬伸阶段,髋关节(172.5°vs 171.4°vs 167.9°,F=14.212,P<0.05)、膝关节(158.0°vs 156.9°vs 150.5°,F=8.810,P<0.05)、踝关节角度(111.0°vs 111.0°vs 106.7°,F=7.366,P<0.05)和起跳角(62.7°vs 63.0°vs 58.8°,F=52.075,P<0.05)显著减小,水平速度(1.70 m/s vs 1.67 m/s vs 1.85 m/s,F=23.174,P<0.05)显著增加;在腾空阶段,髋关节(96.6°vs95.0°vs82.6°,F=40.041,P<0.05)和膝关节角度(90.8°vs 92.4°vs 83.8°,F=27.930,P<0.05)显著减小。结论:外部注意焦点能够有效提升学龄前儿童的立定跳远距离,产生此效果可能与立定跳远预蹲、蹬伸和腾空阶段运动学参数的变化有关。注意焦点的简单改变可能会对学龄前儿童动作技能的练习效果产生影响,教学者在教学中可将学龄前儿童的注意力引导至外部,以促进其动作表现。展开更多
The experimental research, presented in this study, focuses on athletic tests with the purpose to highlight the elastic deformations of the bones of the lower limbs, intending to verify whether the manually treated an...The experimental research, presented in this study, focuses on athletic tests with the purpose to highlight the elastic deformations of the bones of the lower limbs, intending to verify whether the manually treated anatomical structure increases in elasticity, becoming able to accumulate more energy in the loading phase, to then release it in the final phase of the thrust. Introduction: Too often neglected, the bone tissue is capable of deforming. The deformation has a key role in the cushioning and dissipation of stress, a function that is hindered in the event of fascial tension, which will consequently fall on other structures used for the same purpose (Discs, menisci, cartilage, …). Structures that, in the event of increased mechanical stress, could undergo degeneration, inflammation, and injury. Materials and Method: Randomized double-blind selection of 38 people, 18 in the treatment group and 20 in the control group, men and women, aged between 16 and 35, who have been part, for at least one year, of a sports club, with a large space dedicated to jumping in its training program, have been divided into two groups: the treatment group, which was treated to increase the performance of the jump and the control group subjected to mild manual pressures, without any intention. Results: The treatment group had an increase in Standing Long Jump (SLJ) for 3.67% (p Conclusions: This study has shown that an osteopathic manipulative treatment, aimed at increasing jumping performance, can increase the performance of the SLJ.展开更多
文摘Background: Although the standing long jump (SLJ) is a popular physical fitness assessment, it lacks an updated criterion-reference standard. This study generated the first normative SLJ test data for Chinese aged 8 - 18. Methods: From September 2005 to December 2011, comprehensive physical fitness assessments were conducted on 12,712 school students. The SLJ performances were significantly different between boys and girls (all age groups, p < 0.01). Results: The boys performed better than the girls in each age group. The mean difference increased as the age increased, depicting a prominent variance in muscular strength between boys and girls at age 12, and the variances became larger at age 18. Girls in the 70th percenttile performed similarly to boys performing in the 10th percentile. The onset of muscle strength for boys found in this study corresponded to the onset age of testosterone maturation of Chinese boys investigated in previous studies. Linear regression found age and BMI predicting SLJ significantly for boys and girls, explaining better SLJ results in older boy and the effect of their heavy body size. Conclusions: This study indicated a muscular strength difference between genders during growth and added supporting evidence to the hormonal influence of muscle growth during puberty.
文摘Background: This is the first study to publish the normative reference values for assessment of the level of muscular strength through the “standing long jump” test carried out on a large sample of Macedonian school children. The normative values encompass a wide span of years (6 - 18). Methods: The research was realized in a large sample of 12618 school children at the age of 6 to 18 years from Macedonia. The sample was divided in 14 groups, according to chronological age and each age group was divided into two subgroups according to the criteria of gender. For estimation of the morphologic characteristics, the following anthropometric measures have been applied: body height in standing position (cm), body weight (kg), as well as the body mass index (BMI). Children aged 6 or above were invited to take a standing long jump test. Results: Boys show statistically better results in all age categories in the standing long jump test than girls, and these differences become bigger with the increase of age, especially after the 14th year
基金Supported by National NSFC(11501503)Natural Science Foundation of Jiangsu Province of China(BK20131340)+3 种基金China Postdoctoral Science Foundation(2014M560471,2016T90534)Qing Lan Project of Jiangsu Province of ChinaPriority Academic Program Development of Jiangsu Higher Education Institutions(Applied Economics)Key Laboratory of Jiangsu Province(Financial Engineering Laboratory)
文摘In this paper we consider the problem of testing long memory for a continuous time process based on high frequency data. We provide two test statistics to distinguish between a semimartingale and a fractional integral process with jumps, where the integral is driven by a fractional Brownian motion with long memory. The small-sample performances of the statistics are evidenced by means of simulation studies. The real data analysis shows that the fractional integral process with jumps can capture the long memory of some financial data.
文摘目的:以立定跳远动作为例,检验不同注意焦点对学龄前儿童立定跳远结果指标距离和过程指标动作得分的影响,并从运动学角度分析注意焦点影响立定跳远练习效果的潜在机制,探究注意焦点在学龄前儿童基本动作技能教学中的作用。方法:选取46名4.5~6.0岁的学龄前儿童为受试者,采用受试者内平衡的研究设计分别测试这些儿童在内部、外部和无特定注意焦点指令引导下的立定跳远动作,并分别应用Qualisys红外高速运动捕捉系统和Sony摄像机采集学龄前儿童立定跳远的运动学数据和动作视频。结果:1)与对照组和内部注意焦点组相比,外部注意焦点组的立定跳远距离显著增加(97.7 cm vs 98.9 cm vs104.2 cm,F=23.544,P<0.05),但立定跳远动作得分在各组间无显著性差异(F=0.764,P=0.392)。2)与对照组和内部注意焦点组相比,在预蹲阶段,外部注意焦点组的髋关节(77.2°vs73.9°vs 61.5°,F=49.320,P<0.05)和膝关节角度(110.4°vs 113.7°vs 102.6°,F=31.803,P<0.05)显著减小;在蹬伸阶段,髋关节(172.5°vs 171.4°vs 167.9°,F=14.212,P<0.05)、膝关节(158.0°vs 156.9°vs 150.5°,F=8.810,P<0.05)、踝关节角度(111.0°vs 111.0°vs 106.7°,F=7.366,P<0.05)和起跳角(62.7°vs 63.0°vs 58.8°,F=52.075,P<0.05)显著减小,水平速度(1.70 m/s vs 1.67 m/s vs 1.85 m/s,F=23.174,P<0.05)显著增加;在腾空阶段,髋关节(96.6°vs95.0°vs82.6°,F=40.041,P<0.05)和膝关节角度(90.8°vs 92.4°vs 83.8°,F=27.930,P<0.05)显著减小。结论:外部注意焦点能够有效提升学龄前儿童的立定跳远距离,产生此效果可能与立定跳远预蹲、蹬伸和腾空阶段运动学参数的变化有关。注意焦点的简单改变可能会对学龄前儿童动作技能的练习效果产生影响,教学者在教学中可将学龄前儿童的注意力引导至外部,以促进其动作表现。
文摘The experimental research, presented in this study, focuses on athletic tests with the purpose to highlight the elastic deformations of the bones of the lower limbs, intending to verify whether the manually treated anatomical structure increases in elasticity, becoming able to accumulate more energy in the loading phase, to then release it in the final phase of the thrust. Introduction: Too often neglected, the bone tissue is capable of deforming. The deformation has a key role in the cushioning and dissipation of stress, a function that is hindered in the event of fascial tension, which will consequently fall on other structures used for the same purpose (Discs, menisci, cartilage, …). Structures that, in the event of increased mechanical stress, could undergo degeneration, inflammation, and injury. Materials and Method: Randomized double-blind selection of 38 people, 18 in the treatment group and 20 in the control group, men and women, aged between 16 and 35, who have been part, for at least one year, of a sports club, with a large space dedicated to jumping in its training program, have been divided into two groups: the treatment group, which was treated to increase the performance of the jump and the control group subjected to mild manual pressures, without any intention. Results: The treatment group had an increase in Standing Long Jump (SLJ) for 3.67% (p Conclusions: This study has shown that an osteopathic manipulative treatment, aimed at increasing jumping performance, can increase the performance of the SLJ.
