Movements with greater trunk accelerations and their properties during badminton games

Abstract

This study aimed to elucidate the movements requiring greater trunk accelerations and its frequencies during badminton games, and compare the acceleration components among such movements. Trunk acceleration was measured using a triaxial accelerometer during badminton games. The moments that generated >4 G resultant acceleration were extracted, and movements consistent with the extracted moments were identified. We calculated the extracted movement ratio and frequency and compared the resultant, mediolateral, vertical and anteroposterior accelerations between the top five extracted movements. There were 1,342 movements that generated >4 G [mean, 7.72 (95% confidence interval, 7.31–8.14) cases/min]. The top five movements were lunging during underhand strokes with the dominant hand side leg, landing after overhand strokes on the dominant and non-dominant hand side leg, and cutting from a split step using the dominant and non-dominant hand side leg. Landing on the dominant hand side leg had a greater resultant acceleration than the other movements and had the greatest impact during the badminton game. Lunging during underhand strokes on the dominant hand side leg had greater mediolateral acceleration than the other movements. These results reflected the properties of badminton.     

动作识别对运动员心理敏捷性的影响

动作识别运动员在做出动作反应之前,对所知觉的对象进行辨认并将知对象与其他动作区分开来,获得未来动作反应信息的过程。动作识别能力受训练水平的影响,运动员在动作识别能力上的差异是直接影响其在对抗性运动中心理敏捷性或认辞别中工速度的主要因素之一。     

循环练习法在体育课中的应用

体育运动训练是提高学生身体素质的重要因素，改进，丰富教学手段，方法，是上好体育的关键。循环学习法应用到体育课中，容易调动学生的积极性，发挥学生主观能动性，增大运动量及运动密度，合理应用取能良好的燃烧效果。     

体育学新概念——"轻体育"的兴起

在全球经济日趋一体化、各学科知识日益融合、渗透的今天,体育学这门兼具人文与自然科学特点的学科触角逐渐深入到经济学、医学、管理学、美学、艺术等领域,其边缘性、综合性、娱乐性、休闲性、个性化、大众性、终身性、科学性特点已见端倪,生态化体育、休闲体育、大众体育、终身体育、旅游体育等新的体育观念、模式、概念正在形成。这里,本文借鉴“轻音乐”、“轻工业”概念,将体育学具有上述特点的,职业和竞技之外的,符合个人兴趣和愿望,以愉悦身心、增强社会适应能力,实现自我价值、实现社会和个人可持续发展为目标的生态化体育、休闲体育、大众体育、终身体育、旅游体育等,统称为“轻体育”。     

山东体育学院特殊教育体育专业人才社会需求与就业前景探析

通过资料法、调查法对山东省特殊人群的体育开展状况进行分析,对特殊类体育人才的社会需求进行研究,得出体育类特殊教育专业较大的社会需求和广阔就业前景的结论。同时,结合山东体育学院特殊教育专业的培养目标与课程设置提出合理化建议,为本专业的良性发展提供有效的理论依据。     

美国总统体质委员会对美国学校体育的重要影响

运用文献法阐述了美国总统体质委员会产生、发展的历史背景和重大事件 ,以及它对美国学校体育的重要影响。对于我们借鉴他们的有效运作方式和正在我国开展的全民健身运动具有重要的理论和实践意义     

浅谈我国大学体育教学的新特点

在我国高等教育中,大学教育占据极为重要的作用。体育课程又是大学教育中不可缺少的一门公共课,其主要目的是培养大学生各方面的情操,以保证大学生进入社会以后能够积极面对社会的各项工作的潜在需求。在我国的教育环境之下,高等体育教学与初、中等体育教学在一定的程度上存在一定的差异,因此,我国大学体育教育存在一些新的特点。     

对我国体育产业的经济学思考

采用本文文献资料法，对体育产业的内涵及范围，发展现状及存在问题。我国产业发展所具备的条件，发展体育产业的对策和措施等方面进行初步的研究。     

美国大学体育教育理念启示

为解决学校体育的发展遇到的瓶颈,采用文献资料法对美国大学体育教育理念进行了研究,发现美国大学体育不仅有着浓厚的传统和多重目的性的教育价值,而且还具有卓越的竞技水平,同中国理解为单纯德、智、体中的体育有区别,美国的学校体育和竞技体育是紧密联系着的。革新大学体育发展理念,促进学校体育和竞技体育的有机融合,是解决学校体育发展的有效途径之一。     

我国普通高校体育教学改革发展分析

我国新一轮的基础教育课程改革已经全面启动,体育教学作为普通高校教学活动的重要组成部分,也是实施素质教育,培养德、智、体、美全面发展的人才不可缺少的途径。广大体育教师在教学改革实践中进行了多种有益的尝试,虽然取得了一些喜人的成果,但在教学模式、教学思想等方面还存在许多不容忽视的问题。基于以上问题,试图从理论上对此进行探索...     

普通高校体育教学存在的缺失及对策

作为高等教育的重要组成部分,体育越来越受到国家的重视。在相当长的时间内,高校体育教学还存在诸多问题,表现在"大体育观"、体育教学硬件、软件、体育教学理论的缺失等方面。要必须当前的高校体育教学改革进行建构,即转变教学观念,提高教师素质、改革课程设置,完善考试制度、开发创新模式,加强扩展训练、加大体育投资、加强场馆建设。只有这样,才能跟上时代的脚步,提高国民体质、克服体育教学中的困难。     

Non-wear or sleep? Evaluation of five non-wear detection algorithms for raw accelerometer data

ABSTRACT

Detection of non-wear periods is an important step in accelerometer data processing. This study evaluated five non-wear detection algorithms for wrist accelerometer data and two rules for non-wear detection when non-wear and sleep algorithms are implemented in parallel. Non-wear algorithms were based on the standard deviation (SD), the high-pass filtered acceleration, or tilt angle. Rules for differentiating sleep from non-wear consisted of an override rule in which any overlap between non-wear and sleep was deemed non-wear; and a 75% rule in which non-wear periods were deemed sleep if the duration was < 75% of the sleep period. Non-wear algorithms were evaluated in 47 children who wore an ActiGraph GT3X+ accelerometer during school hours for 5 days. Rules for differentiating sleep from non-wear were evaluated in 15 adults who wore a GeneActiv Original accelerometer continuously for 24 hours. Classification accuracy for the non-wear algorithms ranged between 0.86–0.95, with the SD of the vector magnitude providing the best performance. The override rule misclassified 37.1 minutes of sleep as non-wear, while the 75% rule resulted in no misclassification. Non-wear algorithms based on the SD of the acceleration signal can effectively detect non-wear periods, while application of the 75% rule can effectively differentiate sleep from non-wear when examined concurrently.     

体育主体性教学理论的研究

主体性体育教学是素质教育与现代教育思想结合的产物,其宗旨是充分发挥学生的主观能动性,使每个学生都能积极主动地参与到体育学习和锻炼中来,保证每个学生身心得到全面、和谐的发展。     

时尚体育在高校体育课开展中的优势与注意事项

通过文献资料法阐述时尚体育的概念、特点,分析时尚体育在高校体育课开展中对学生、教师和学校的产生的积极效应,并提出时尚体育进入高校的注意事项。     

我国学校民族传统体育教学的现实路径解读

运用教育学的知识和方法,对我国学校民族传统体育教学的现实路径进行了详细的解读。认为当前学校民族传统体育教学活动、组织形式和评价机制均存在不同程度的问题。     

新时期"体教结合"的现实需要与长远发展

"体教结合"经过多年的探索与实践,取得了一定成绩,新时期仍面临着很多问题.加强和完善"体教结合"的管理机制,加强学校体育,改革竞赛制度,转移高校高水平运动队招生重心,才能保证"体教结合"的长远发展,培养更多优秀体育后备人才.     

Physical movement demands of elite-level netball match-play as measured by an indoor positioning system

ABSTRACT

Physical movement demands in elite netball match-play have been limited to notational analysis or accelerometer-derived measures, due in part to the indoor environment in which they are played. Commercially available local positioning systems (LPS) using ultra-wideband communication have been designed to bring similar capabilities as global positioning systems (GPS) to indoor environments. This study aims to quantify both spatiotemporal and traditional accelerometer-derived measures, to assess the movement demands of all playing positions, during Australian national netball league matches. Total distance, metreage per minute, acceleration density, acceleration density index, acceleration load, jumps, velocity bands, acceleration bands and PlayerLoad variables have been presented for each position. Mean total distance-covered in match-play differed substantially between positions. Centre position accumulated the highest mean distance (5462.1 ± 169.4 m), whilst the Goal Shooter consistently covered the lowest mean distance (2134 ± 102.6 m). Change of direction relative to movement area was highest for the two most restricted positions based on average acceleration per 10 m covered during match-play (Goal Shooter; 7.21 ± 0.88 m · s ^{? 2} and Goal Keeper; 6.75 ± 0.37 m · s ^{? 2}, remaining positions; 5.71 ± 0.14 m · s ^{? 2}). The positional profiles outlined in this study can assist skill and conditioning coaches to prescribe training sessions that will optimise the athlete’s physical preparation for the demands of competition.     

新时期“体教结合”的现实需要与长远发展

“体教结合”经过多年的探索与实践,取得了一定成绩,新时期仍面临着很多问题。加强和完善“体教结合”的管理机制,加强学校体育,改革竞赛制度,转移高校高水平运动队招生重心,才能保证“体教结合”的长远发展,培养更多优秀体育后备人才。     

山东省体育学校参加选拔的体育后备人才身体素质动态分析

采用数理统计、文献资料和对比分析等方法，对山东省体育学校1999-2002年4285名参加选拔的体育后备人才的素质进行了分析研究，结果显示：四年来中专学生的各项身体素质成绩均有不同程度的下降，大专学生除男生立定跳远和原地推铅球成绩有显著性提高外，其余变化不大；男生大专学生成绩总体优于中专，女生立定跳远和原地推铅球成绩优于中专，而100m、800m成绩比中专差。     

Assessment of step accuracy using the Consumer Technology Association standard

The purpose of this study was to compare the accuracy of commercially-available physical activity devices when walking and running at various treadmill speeds using CTA 2056: Physical Activity Monitoring for Fitness Wearables: Step Counting, standard by the Consumer Technology Association (CTA). Twenty participants (10 males and 10 females) completed self-paced walking and running protocols on the treadmill for five minutes each. Eight devices (Apple iWatch series 1, Fitbit Surge, Garmin 235, Moto 360, Polar A360, Suunto Spartan Sport, Suunto Spartan Trainer, and TomTom Spark 3) were tested two at a time, one per wrist. Manual step counts were obtained from video to serve as the benchmark. The mean absolute percent error (MAPE) was calculated during walking and running. During walking, three devices: Fitbit Surge (11.20%), Suunto Sport (22.93%), and TomTom (10.11%) and during running, one device, Polar (10.66%), exceeded the CTA suggestion of a MAPE < 10%. The Moto 360 had the lowest MAPE of all devices for both walking and running. The devices tested had higher step accuracy with running than walking, except for the Polar. Overall, the Apple iWatch series 1, Moto 360, Garmin, and Suunto Spartan Trainer met the CTA standard for both walking and running.