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1.
运用文献资料法、专家访谈法等研究方法,对我国各省份学生体质健康测试第三方机构督查的独立性进行研究。通过对我国各省份学生体质健康测试第三方机构督查独立性的现状、问题、原因及对策的探索,在政策上,可以为教育行政部门改革提供决策思路和参考,在实践上,可以提高学生体质健康测试督查的权威性和有效性,倒逼学生体质健康测试的规范化实施。研究发现,当前我国各省份学生体质健康测试第三方机构督查的独立性差,主要体现在第三方机构与教育厅存在行政隶属关系、存在利益关联、第三方机构工作自主性差3个方面。影响学生体质健康测试第三方机构督查独立性的因素主要为中国传统文化对体育和公民意识的漠视、当事方的利益诉求对第三方机构督查独立性的限制、法规制度缺位、第三方机构发育程度低等。提出保障学生体质健康测试第三方机构督查独立性的对策:教育部对第三方机构督查的责权划分做出设计安排,培养公民意识,扩宽经费来源渠道,第三方机构完善自身治理。  相似文献   
2.
因果要素关联视域下社交媒体倦怠用户画像模型构建   总被引:1,自引:1,他引:0  
[目的/意义]探究社交媒体倦怠的原因要素和结果要素标签,分析各要素间的相互作用关系,扩展用户信息行为的理论研究范畴,为企业深入了解用户社交媒体倦怠发展态势提供指导。[方法/过程]基于信息生态理论,提取"信息人、信息、信息环境和信息技术"4个信息生态因子维度的社交媒体用户画像标签;根据用户心理特征和行为表现,抽取用户画像情感和行为标签,构建社交媒体倦怠用户画像模型。[结果/结论]透过社交媒体用户消极使用和负面情感变化的典型社会现象,对用户画像模型进行整合分析与关系凝练,证明本研究社交媒体倦怠用户画像模型与S-S-O理论框架具有一致性,并根据实际进行理论上的拓展和应用。  相似文献   
3.
研究目的:探究拖重物跑训练手段对短跑运动员的身体素质、途中跑阶段的技术特征及下肢环节肌肉力量的影响,深入认识其对短跑途中跑技术和专项力量的作用机制。研究方法:对14名男子二级左右水平短跑运动员进行为期8周每周3次6%~10% BM负荷的拖重物跑训练,采用高速摄像分析法、等动肌力测试法分析运动员身体素质;支撑阶段髋、膝、踝关节运动学参数和下肢各环节肌肉力量实验前后的变化情况。结果:(1)实验后运动员30m、60m、立定跳远、立定三级跳远等身体素质及专项成绩显著提高;(2)步长、重心水平速度显著性提高,两大腿剪绞平均速度提高、单步时间减少;支撑阶段最小膝、踝角显著降低,角速度提高;(3)髋、膝关节伸/屈肌群PT/BW、AP除膝关节60°/sPT/BW值未见统计学意义,其余各角速度下PT/BW、AP均呈显著性差异,踝关节跖屈肌群各角速度下PT/BW值显著提高,跖屈肌群60°/s速度下AP提高,背屈肌群AP略降低。结论:适宜负荷的拖重物跑训练可显著改善短跑运动员运动素质、提高运动成绩;有利于提高髋关节剪绞-制动力量,使膝、踝关节处于低位超等长"屈蹬"状态;提高了髋、膝关节屈伸肌群快速主动收缩能力及踝关节跖屈肌群退让性快速收缩能力。  相似文献   
4.
BackgroundCompassion fatigue (i.e., a worker’s diminished ability to empathize with clients) is common among “helping workers” and can result in psychological detachment from clients as a coping mechanism.ObjectiveIn the present research, we explored the relationship between social workers’ compassion fatigue and years of job experience on hypothetical child custody case judgments.Participants and settingIn two separate studies, individuals with experience working with children in child dependency court (predominantly social workers, Study 1: N = 173, Study 2: N = 119) were recruited on Amazon’s Mechanical Turk and read a vignette depicting a mother attempting to regain custody.ResultsSupporting hypotheses, compassion fatigue significantly mediated the relationship between increased years of social worker job experience on recommendations that a neglectful mother receive custody, Indirect Effect = .06, CIs [.026, .127] (Study 1). We also found preliminary support for our hypothesized theoretically derived serial path model, in which (a) social worker compassion fatigue predicts anticipated secondary traumatic stress associated with the child neglect case, B = .54, p = .0001; (b) secondary traumatic stress predicts detachment from the neglected child, B = .27, p = .0003; (c) detachment from the child predicts job efficacy cynicism B = .65, p < .0001; and (d) job efficacy cynicism predicts decisions to allocate custody to the neglectful mother, B = .46, p = .005 (Study 2).ConclusionOur research shows that compassion fatigue among social workers may change the lens through which they perceive cases of child abuse.  相似文献   
5.
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   
6.
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 (< .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   
7.
目的探讨下肢间歇负压干预对赛艇运动员心率变异性(HRV)相关指标和儿茶酚胺的影响。方法将国家赛艇队的14名运动员分为试验组和对照组,试验组运动员每周用间歇负压干预5 d,持续4周,对照组无其他干预方式。试验期间均对2组运动员进行HRV相关指标和儿茶酚胺的测试。结果试验前2组运动员各指标均无统计学差异。开始干预后2组的变化如下:①在时域指标中,试验组正常窦性R-R间期标准差(SDNN)在第3周时高于对照组(P<0.05)。②在频域指标中,试验组高频(HF)值在第2周和第3周时高于对照组(P<0.05),而其高频与低频比(LF/HF)在第1、3和4周时低于对照组(P<0.05)。③2组儿茶酚胺组内、组间比较均无统计学差异,但试验组儿茶酚胺下降程度比对照组高。结论4周的间歇负压干预对运动员自主神经系统功能的恢复有明显促进作用,对儿茶酚胺的分泌也具有抑制趋势;这有利于降低运动员心脏负荷,促进运动后的生理恢复。  相似文献   
8.
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   
9.
The aim of the study was to evaluate the effect of maximal specific physical effort on postural balance and rifle stability in biathletes in a standing shooting position. The study included 10 junior elite biathletes. The measurements were taken with the Vicon system and AMTI force platform. Postural balance and rifle stability characteristics were determined at rest as well as 1 and 5 min post maximal specific physical effort which was performed on a ski ergometer and continued until exhaustion. Maximal physical effort exerted a significant effect on all examined postural sway and rifle sway characteristics. The duration of the post-exercise changes was longer than 5 minutes. Higher post-effort rifle sway was observed in the vertical direction than in the across the shooting line direction. Post-effort postural balance impairment in the shooting line was much greater than in the across the shooting line direction. Moreover, a strong correlation was found between postural balance and rifle stability. Maximal physical effort influenced postural balance and rifle stability during aiming. Rifle sway during aiming in a standing shooting position seems to be coordinated with the postural sway of the biathlete’s body. Thus, an increase in postural sway contributes to greater sway and lesser stability of the rifle.  相似文献   
10.
Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO2) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La?]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males.  相似文献   
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