我国高危险性体育项目的立法缺陷及其完善     

汪全胜  宋琳璘  张奇 《武汉体育学院学报》2020,54(6):46-53

高危险性体育项目相对一般体育项目而言，是具有危险性大、专业技术性强、安全保障要求高等特点的体育活动。我国对高危险性体育项目有一定的法律规制，但存在顶层设计缺失、法律制度之间的冲突与不一致、可操作性不足等问题。这些制度缺陷产生的根源在于对立法必要性的认识不足、立法不作为，缺乏有效的立法监督机制等，现有制度的缺陷与不足会影响我国高危险性体育项目的发展，难以满足人们体育文化活动的需要。鉴于此，我国应逐步完善高危险性体育项目的法律规制，包括完善高危险性体育项目的审定主体，明确经营高危险性体育项目的主体范围、完善高危险性体育项目的行政许可条件、强化高危险体育项目行政监管以及风险防范等。  相似文献   

不同负荷运动训练对大鼠骨骼肌线粒体三羧酸循环的影响及其机制研究     

李洁  杨静  赵丽丽 《武汉体育学院学报》2019,53(5):88-94

目的：探讨不同负荷运动训练对大鼠骨骼肌线粒体三羧酸循环的影响及其机制。方法：将雄性Wistar大鼠50只随机均分为5组：安静对照组（C）、低负荷运动训练组（LT）、中等负荷运动训练组（MT）、高负荷运动训练组（HT）和极高负荷运动训练组（ST），每组10只。各运动组分别进行6周的跑台运动训练。训练方案结束后，取腓肠肌样本，提取线粒体，测定线粒体柠檬酸合成酶（CS）、异柠檬酸脱氢酶（ICD）和α-酮戊二酸脱氢酶（α-KGDHC）活性；线粒体Ga²⁺含量、胞浆NADH、NAD⁺、ATP和ADP含量，以及ICD mRNA转录水平。结果：（1）不同负荷运动训练组线粒体CS、ICD和α-KGDHC的活性均显著高于安静对照组（P < 0.01），且CS和ICD活性由高到低顺序均为：MT组 > HT组 > ST组 > LT组 > C组，α-KGDHC活性由高到低顺序为：HT组 > MT组 > ST组 > LT组 > C组。（2）不同负荷运动训练组线粒体Ca²⁺ 含量均显著高于安静对照组（P < 0.01），其含量由高到低顺序为：MT组 > HT组 > ST组 > LT组 > C组；胞浆NADH/NAD⁺和ATP/ADP的比值均显著低于安静对照组（P < 0.01），其比值由低到高顺序为：MT组 < ST组 < HT组 < LT组 < C组。（3）不同负荷运动训练组ICD mRNA转录水平均高于安静对照组（P < 0.01），其水平由高到低顺序为： MT组 > HT组 > ST组 > LT组 > C组。结论：低负荷、中等负荷、高负荷及极高负荷运动训练均可提高大鼠骨骼肌线粒体三羧酸循环功能，且中等负荷运动训练效果最佳。其机制与胞浆NADH/NAD⁺和ATP/ADP比值、线粒体摄钙能力及限速酶基因的表达有关。  相似文献   

Transforming,storing and consuming athletic experiences: a coach’s narrative of using a video application     

C. Cronin  A.E. Whitehead  S. Webster  T. Huntley 《Sport, Education and Society》2019,24(3):311-323

The analysis of sport performance in competitive contexts has become synonymous with the use of a range of software applications and hardware e.g. heart rate monitors and gps systems. With the prevalence of technology in mind, a small but growing corpus of literature has begun to consider this phenomenon and its influence upon the coaching process. This study adds to this literature by detailing the autoethnographic experiences of a case study coach; Derek. A contextualised and richly described narrative account of Derek’s experience of using coaching applications is provided. Analysis of Derek’s narrative suggests that technology can be a useful means by which individuals make sense of their experience. Specifically, (1) technology can be a ‘ready-to-hand’ instrument that enhances the coaching process. Unfortunately, (2) technology may become the only and ‘calculative’ means by which individuals come to understand their performance. In such instances, it is important to note that (3) the videos we use to understand our performance are transformed and incomplete representations of lived athletic experiences. Thus, Derek’s story illustrates how technology can be both an enabler and barrier to athletes who wish to holistically understand their own lived experiences and engage in coach-athlete relationships. The accompanying analysis draws upon concepts from Heideggerian philosophy to add insight into the use of technology within the coaching process. In so doing, the study prompts coaches to critically view their coach-athlete relationships as situated in a wider world which contains, and can be mediated by, technology. In addition, Derek’s story (re)directs researchers and coaching practitioners interested in technology to a useful literature (philosophy of technology) which may further inform their understanding of coach-athlete relationships.  相似文献   

初中体育“翻转课堂”教学策略分析     

朱小明 《当代体育科技》2020,(12):190-191

翻转课堂是当代教育理念下发展形成的一种新型教学方式,将其合理应用于我国初中体育教学较传统教学方式能够更好地满足当代学生的体育学习要求。但由于该教学理念在我国刚刚进入初期应用阶段,很多细节方面仍有待完善,因此,教师还应进行细致研究,加强新型教育工作实践,制定科学、合理的翻转课堂教学策略,提高初中体育教学工作效率。  相似文献   

瑜伽对田径运动员运动性疲劳恢复的可行性分析     

刘平  苑廷刚  程泓人  韩鹏鹏 《体育科技文献通报》2020,(1):46-48

本文使用文献资料法、综述法、比较法、逻辑分析法等科研方法,针对瑜伽对心理和生理功能的作用和运动员的运动性疲劳两方面进行综述对照研究,探究得出:将瑜伽放松练习运用于田径运动员运动性疲劳恢复中的意义,并且提出将瑜伽练习运用于田径运动员的运动性疲劳恢复训练当中。  相似文献   

3-min all-out effort on cycle ergometer is valid to estimate the anaerobic capacity by measurement of blood lactate and excess post-exercise oxygen consumption     

Alessandro Moura Zagatto  Paulo Eduardo Redkva  Rodrigo Araújo Bonetti de Poli  Joel Abraham Martinez González  Jeniffer Zanetti Brandani  Thiago Penedo 《European Journal of Sport Science》2019,19(5):645-652

The purpose of this study was to investigate the use of a single 3-min all-out maximal effort to estimate anaerobic capacity (AC) through the lactate and excess post-exercise oxygen consumption (EPOC) response methods (AC_{[La^?]+EPOCfast}) on a cycle ergometer. Eleven physically active men (age?=?28.1?±?4.0?yrs, height?=?175.1?±?4.2?cm, body mass?=?74.8?±?11.9?kg and ?O_2max?=?40.7?±?7.3?mL?kg^?1?min^?1), participated in the study and performed: i) five submaximal efforts, ii) a supramaximal effort at 115% of intensity of ?O_2max, and iii) a 3-min all-out maximal effort. Anaerobic capacity was estimated using the supramaximal effort through conventional maximal accumulated oxygen deficit (MAOD) and also through the sum of oxygen equivalents from the glycolytic (fast component of excess post-exercise oxygen consumption) and phosphagen pathways (blood lactate accumulation) (AC_{[La^?]+EPOCfast}), while during the 3-min all-out maximal effort the anaerobic capacity was estimated using the AC_{[La^?]+EPOCfast} procedure. There were no significant differences between the three methods (p?>?0.05). Additionally, the anaerobic capacity estimated during the 3-min all-out effort was significantly correlated with the MAOD (r?=?0.74; p?=?0.009) and AC_{[La^?]+EPOCfast} methods (r?=?0.65; p?=?0.029). Therefore, it is possible to conclude that the 3-min all-out effort is valid to estimate anaerobic capacity in physically active men during a single cycle ergometer effort.  相似文献   

Corticospinal changes induced by fatiguing eccentric versus concentric exercise     

Yoann M. Garnier  Christos Paizis  Romuald Lepers 《European Journal of Sport Science》2019,19(2):166-176

The present study assessed neuromuscular and corticospinal changes during and after a fatiguing submaximal exercise of the knee extensors in different modes of muscle contraction. Twelve subjects performed two knee extensors exercises in a concentric or eccentric mode, at the same torque and with a similar total impulse. Exercises consisted of 10 sets of 10 repetitions at an intensity of 80% of the maximal voluntary isometric contraction torque (MVIC). MVIC, maximal voluntary activation level (VAL) and responses of electrically evoked contractions of the knee extensors were assessed before and after exercise. Motor evoked potential amplitude (MEP) and cortical silent period (CSP) of the vastus medialis (VM) and rectus femoris (RF) muscles were assessed before, during and after exercise. Similar reductions of the MVIC (?13%), VAL (?12%) and a decrease in the peak twitch (?12%) were observed after both exercises. For both VM and RF muscles, MEP amplitude remained unchanged during either concentric or eccentric exercises. No change of the MEP amplitude input–output curves was observed post-exercise. For the RF muscle, CSP increased during the concentric exercise and remained lengthened after this exercise. For the VM muscle, CSP was reduced after the eccentric exercise only. For a similar amount of total impulse, concentric and eccentric knee extensor contractions led to similar exercise-induced neuromuscular response changes. For the two muscles investigated, no modulation of corticospinal excitability was observed during or after either concentric or eccentric exercises. However, intracortical inhibition showed significant modulations during and after exercise.  相似文献   

The impact of physiological load on anticipation skills in badminton: From testing to training     

D. B. Alder  D. P. Broadbent  J. Stead  J. Poolton 《Journal of sports sciences》2019,37(16):1816-1823

Research remains unclear on the impact of physiological load on perceptual-cognitive skills in sport. Moreover, no study has examined the training of perceptual-cognitive skills under physiological load. The current study comprised two phases. Firstly, we examined the impact of badminton-specific physiological load on anticipatory skills in expert badminton players (n = 13), including key underlying mechanisms, such as gaze behaviour. Under high physiological load, participants displayed less efficient visual search behaviour and showed a reduction in response accuracy. Secondly, we examined the effects of combining perceptual-cognitive simulation training with the high physiological load. Ten of the expert badminton players were assigned to a combined training group, where the simulation training and the physiological load intervention occurred simultaneously or an independent training group, whereby the two components were completed independently. The combined training group showed a positive change in the efficiency of their visual search behaviours compared to the independent training group, but no significant performance improvements were found. Overall, findings demonstrate that high physiological load is detrimental to experts’ anticipatory skills. However, combining perceptual-cognitive simulation training with high physiological load can potentially negate these debilitating effects.  相似文献   

一种改进的基于峭度指标的FastICA算法     

孟令博  耿修瑞  杨炜暾 《中国科学院大学学报》2019,36(3):410-416

基于峭度指标的FastICA算法具有较快的收敛速度和较高的计算效率，被广泛应用于多光谱图像的特征提取。经典的FastICA算法基于固定点迭代法得到图像的各个独立成分，在迭代过程中，每一个独立成分的求解都需要所有像元的参与。因此，当数据量较大或图像中像元较多时，FastICA的计算量很大，此时它的速度优势就会大打折扣。遥感数据一般都具有较大的尺寸，因此如何将FastICA直接应用于遥感数据，是一个具有实际意义的问题。通过引入多光谱图像协峭度张量的概念，将FastICA的固定点迭代问题转化为代数形式的张量计算，避免每次迭代过程中需所有像元参与的缺陷，因而大大降低计算复杂度。多光谱图像实验结果表明，该算法明显快于传统的基于峭度指标的FastICA算法。  相似文献   

The effect of smartphones and playing video games on decision-making in soccer players: A crossover and randomised study     

Leonardo S. Fortes  Dalton De Lima-Junior  Lenamar Fiorese  José R. A. Nascimento-Júnior  Arnaldo L. Mortatti  Maria E. C. Ferreira 《Journal of sports sciences》2020,38(5):552-558

ABSTRACT

The objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (p < .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes.  相似文献