The validation and application of Inertial Measurement Units to springboard diving

Inertial Measurement Units (IMUs) may offer an ecologically valid, reliable, and practical method for biomechanical performance analysis. With such potential in mind, Part 1 of this study examined the accuracy of IMUs gyroscopes with an optical system (Cortex 3.3). A calibration formula standardised the IMUs angular velocity output with the optical system. The percentage differences between the two measures = 0.5% (p < 0.05), suggest IMU’s efficacy for application. In Part 2, the aim was to examine and understand how dive flight angular velocity time series plots change and increase according to dive degree of difficulty. With IMUs attached to three competitive divers performing forward somersault dives, dive flight kinematics were assessed. Biomechanically, a 4½ tuck somersault dive differed to lower degree of difficulty dives in terms of: (1) a rotational delay immediately after takeoff (to gain greater vertical translation); (2) increased total time of flight; (3) greater muscle effort to resist increased centrifugal forces produced by the increased angular velocity (1,090 °/s); and (4) greater eccentric control during deceleration allow a safe and vertical entry into the water. IMUs can be effectively utilised and integrated into contexts such as springboard diving for performance analysis and optimisation purposes.     

我国110m栏运动员过栏技术参数的分析

本文对我国110m栏运动员起跨技术参数角度的解析数据,采用灰色关联的方法进行研究,揭示健将级、一级运动员之间的差别。     

刘翔110m栏第5栏跨栏步技术的依据研究

本文从理论和实践相结合的角度,通过有关资料的对比分析,对我国男子跨栏运动员刘翔110m栏跨栏跑的个性特征进行分析,结果表明：要对刘翔的跨栏步技术进行分析,应该分析第5栏更合适.     

The continuous measurement of the springboard reaction force in gymnastic vaulting

A new method was established for the continuous measurement of force applied from a springboard to a gymnast in vaulting (board reaction force). Male gymnasts performed a handspring vault using a springboard mounted on force platforms. A high-speed video camera sampled the springboard motion at 500 Hz. The springboard was initially partitioned into 29 segments. The force due to the accelerative motion of the springboard was determined by summing the forces of the individual segments. The board reaction force acting on the gymnast was calculated by subtracting the force due to the accelerative motion of the springboard and weight from the force recorded by the force platform. The new method succeeded in illustrating transient changes of the board reaction force. The horizontal and vertical components of the peak values of the board reaction force were three and two times greater respectively than the average values. A series of tests was conducted to determine whether the number of segments of the springboard model could be reduced without affecting accuracy. A model consisting of only four segments produced almost the same accuracy as the 29-segment model. The simplified model is recommended as a more efficient method to measure board reaction force.     

运用心理训练克服跨栏中的不良心理

在跨栏训练和比赛中,往往会产生一些不良的心理反映。通过心理训练的不同方法,使学生掌握调节自己心理状态的各种方法,以便在训练和比赛中取得更好的成绩。在以往的教学与训练中,教师更多的注重身体素质和技术动作的训练,往往忽视了对学生的心理训练,以致于在比赛时不能发挥最佳水平。所以心理训练对学习掌握运动技术和提高跨栏成绩具有重要作用。     

The continuous measurement of the springboard reaction force in gymnastic vaulting

Abstract

A new method was established for the continuous measurement of force applied from a springboard to a gymnast in vaulting (board reaction force). Male gymnasts performed a handspring vault using a springboard mounted on force platforms. A high-speed video camera sampled the springboard motion at 500 Hz. The springboard was initially partitioned into 29 segments. The force due to the accelerative motion of the springboard was determined by summing the forces of the individual segments. The board reaction force acting on the gymnast was calculated by subtracting the force due to the accelerative motion of the springboard and weight from the force recorded by the force platform. The new method succeeded in illustrating transient changes of the board reaction force. The horizontal and vertical components of the peak values of the board reaction force were three and two times greater respectively than the average values. A series of tests was conducted to determine whether the number of segments of the springboard model could be reduced without affecting accuracy. A model consisting of only four segments produced almost the same accuracy as the 29-segment model. The simplified model is recommended as a more efficient method to measure board reaction force.     

多媒体手段在跨栏教学中的应用

近年来多媒体教学在体育教学中的应用开辟了体育教学的新领域。本文主要通过采用实验研究法,运用多媒体进行跨栏教学。结果表明,与传统教学方法相比,它能丰富教学方法、手段,活跃课堂气氛,增强学生学习积极性和兴趣,大大提高体育教学效果。     

跨栏跑项目专项力量素质的生理学特征

从跨栏跑的项目特点出发,采用文献资料法、逻辑分析法等研究方法对跨栏跑项目进行分析,指出跨栏跑专项力量素质的内容,并对其生理学特征进行了分析,提出了在跨栏跑项目的专项力量训练中应注意的事项。     

A mathematics-based new penalty area in football: tackling diving

ABSTRACT

A novel penalty area (PA) for football (soccer) is proposed; it is based on considering mathematically the actual scoring possibility on the 2 dimensions near the goal. It is shown that the 150-year-old rectangular area is mathematically disproportionate; this can be causing too much diving or simulation by players around the goal and also too many matches that are decided unfairly. The goal or objective is to reduce these problems – and others – with a new PA based on the proposed scoring potential measure which is in turn based on the angle towards the goal line (between posts) and the distance to the centre of this line.     

试谈跨栏跑速度训练的几个特点

文章运用文献资料研究法,通过对跨栏跑速度训练的研究,发现跨栏运动员必须重视大强度的速度训练,必须重视速度训练与跨栏技术的有效结合,并提出发展快速力量有利于跨栏速度的提高。     

跨栏项目技术评定量化标准的方法

采用文献资料与教理统计相结合的研究方法,对跨栏跑技术评定各项指标的选择、量化指标的建立,以及实际运用等问题,进行了阐述。     

对跨栏跑中起跨腿提拉技术特点分析

为探讨跨栏跑中,起跨腿提拉动作的技术特点,运用文献资料法和逻辑分析法从运动生物力学角度进行分析。研究发现,两种起跨腿提拉技术在其目的上具有相同性,但是在提拉完成的效果上具有差异性,原因在于采用旋提技术的起跨腿高抬能够增大摆动腿蹬地的力量,其同侧髋产生的最大的转动角,减小了起跨腿提拉过程中的转动惯性力量,同时臀大肌被预先拉长,加快了起跨腿下压着地的速度,保证了合理的栏间三步的节奏;而直接提拉技术的起跨腿平移提拉不能增大摆动腿蹬地的力量,其同侧髋未达到最大转动幅度,增大了起跨腿提拉过程中的转动惯性力量,同时臀大肌未被预先拉长,使起跨腿在下压着地过程中的摆动速度相对较慢,影响栏间三步节奏。     

帮助学生克服跨栏跑时“恐惧心理”的教学方法

采用问卷与实验相结合的方法,针对学生跨栏跑时“恐惧心理”产生的原因及外在表现,论述了教学中克服学生“恐惧心理”的具体方法。     

基于支持向量机的刘翔110 m栏成绩预测

提出了一种基于最小二乘支持向量机(LS-SVM)的刘翔专项成绩预测的新方法.收集2000年至2007年59次刘翔110m栏成绩组成整个数据集,前5次的成绩用来预测第6次的成绩,由前54次成绩建立LS-SVM成绩预测模型,运用建立的LS-SVM成绩模型预测最后5次的成绩.结果表明:提出的LS-SVM成绩预测方法是有效的.刘翔110m栏成绩预测可为其训练乃至世界优秀跨栏运动员的训练提供理论参考.     

小群体教学法在高校跨栏课程中的应用探索

在充分介绍了小群体教学法基本流程和内容的前提上,结合中国体育专业学生的实际水平和群体特征,通过分为实验班和对照班进行跨栏跑教学,结果说明小群体教学法可以为学生提供较大自由发挥的空间,通过学生之间的相互配合交流来激发学生学习体育技能的兴趣。     

浅谈女生跨栏跑教学心理障碍的克服

在田径教学中 ,跨栏跑有一定难度和有一定危险性 ,使一些心理素质和身体素质差的女生对学习跨栏跑产生畏惧情绪。这种情绪如不及时解决就会影响学生的学习热情 ,引发恐惧心理 ,从而影响整个教学计划的完成。因此 ,本文结合自己的教学实践 ,就跨栏跑教学中产生惧栏的心理原因及克服恐惧心理的具体方法进行初步的探讨。     

中国竞技跳水运动面临的挑战与应对策略

以国内重大比赛调研为基础,结合对教练员、裁判员和管理人员的访谈,并以国际重大比赛的数据分析为依据,分析了中国竞技跳水运动现阶段所面临的三大严峻挑战,提出了相应的应对策略。     

The oxygen-conserving potential of the diving response: A kinetic-based analysis

We investigated the oxygen-conserving potential of the human diving response by comparing trained breath-hold divers (BHDs) to non-divers (NDs) during simulated dynamic breath-holding (BH). Changes in haemodynamics [heart rate (HR), stroke volume (SV), cardiac output (CO)] and peripheral muscle oxygenation [oxyhaemoglobin ([HbO₂]), deoxyhaemoglobin ([HHb]), total haemoglobin ([tHb]), tissue saturation index (TSI)] and peripheral oxygen saturation (SpO₂) were continuously recorded during simulated dynamic BH. BHDs showed a breaking point in HR kinetics at mid-BH immediately preceding a more pronounced drop in HR (?0.86 bpm.%^?1) while HR kinetics in NDs steadily decreased throughout BH (?0.47 bpm.%^?1). By contrast, SV remained unchanged during BH in both groups (all P > 0.05). Near-infrared spectroscopy (NIRS) results (mean ± SD) expressed as percentage changes from the initial values showed a lower [HHb] increase for BHDs than for NDs at the cessation of BH (+24.0 ± 10.1 vs. +39.2 ± 9.6%, respectively; P < 0.05). As a result, BHDs showed a [tHb] drop that NDs did not at the end of BH (?7.3 ± 3.2 vs. ?3.0 ± 4.7%, respectively; P < 0.05). The most striking finding of the present study was that BHDs presented an increase in oxygen-conserving efficiency due to substantial shifts in both cardiac and peripheral haemodynamics during simulated BH. In addition, the kinetic-based approach we used provides further credence to the concept of an “oxygen-conserving breaking point” in the human diving response.     

对我国110m跨栏技术特征的分析

结合现代跨栏技术原理和国内优秀110m跨栏运动员比赛的运动学参数,阐明良好跨栏跑技术的特征,为评价运动员跨栏跑技术的合理性提供可靠的依据.     

我国部分优秀男子110m栏运动员第1栏与第5栏的跨栏步速度的灰色优势比较分析

本文采用文献资料法、灰色优势分析法，以我国部分优秀男子110m栏运动员的跨栏步速度(跨栏步的步长／腾空时间)为主因素，以跨栏步的起跨阶段的16个运动数据，腾空阶段的6个运动数据，下栏着地的14个运动数据，跨栏步的4个运动数据为子因素。采用灰色关联度和灰色优势分析等对原始数据进行处理，利用优势分析的结果找出影响第1栏、第5栏跨栏步速度的主要子因素进行比较分析，为跨栏步速度的提高，提供训练的理论依据。