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1.
社会快速发展、生活日趋便捷背景下,医学生面临着生理和心理上的问题,且医学生由于专业特殊性,认知能力中记忆力的重要性被凸显出来。本文运用查阅文献资料、专家访谈、问卷调查、逻辑分析等研究方法,探究从运动处方角度出发的实验--"高强度间歇运动对医学生不同时长记忆力的影响"具有多方面重要性。同时建议医学院校应当跟据研究结果和实际情况,制定科学、合理的运动训练计划,为医学生生理和心理健康提供保障。  相似文献   
2.
田径运动是所有运动的基础运动,是促进身体健康的重要手段,对实现健康中国战略有重要的意义。本研究以普通高校大学体育田径运动的教学及发展路径为切入点,对几所高校进行调查分析,找出田径运动发展过程中存在的问题,并提出相关建议,使田径运动在高校更好地发展,促进健康中国战略目标的贯彻实施。  相似文献   
3.
审视中国古代镖局中镖师武术的技术特征、传承传播、发展演变,能够再现早期武术发展状况,丰富武术历史研究内容,还可总结历史经验,为新时代推广武术、弘扬武术文化提供借鉴。运用文献资料法和历史分析法,就镖局对清末民初武术发展之推动作用进行分析。认为,镖局是实现武术功能职业化转型的重要组织,推动了武术的顺时代创新演变,开辟了多元的武术传播途径,稳固了师徒传承方式,推动了武术价值的多元化发展,促进了暗器、轻功等罕见武技的深造与传承,为“以武报国”提供了重要的物力支撑。  相似文献   
4.
利用UAS/hand-gal4系统构建果蝇心脏Nmnat基因特异性过表达,研究心脏Nmnat基因过表达联合耐力运动对高脂膳食诱发脂毒性心肌症的影响,并分析其分子机制。方法:雄性w^1118和NmnatUAS系果蝇分别与雌性hand-Gal4杂交,收集F1代心脏Nmnat正常表达(hand>w^1118)和过表达(hand>Nmnat)处女蝇,饲养至15 d后开始进行耐力运动(E)和高脂膳食(HFD),并分为hand>w^1118、hand>w^1118+E、hand>w^1118+HFD、hand>w^1118+HFD+E、hand>Nmnat、hand>Nmnat+E、hand>Nmnat+HFD、hand>Nmnat+HFD+E共8组,每组410只。ELISA检测心脏TAG、NAD+、SIR2蛋白去乙酰化、SOD活力和MDA水平,qRT-PCR检测心脏相关基因mRNA表达,M-mode检测心脏功能情况。结果:hand>w^1118+HFD+E果蝇心脏的Nmnat、dFoxo、bmm表达、NAD+水平、SIR2去乙酰化、SOD活力、缩短分数高于hand>w^1118+HFD(P<0.05或P<0.01),且d FAS和Col4al表达、TAG和MDA水平、心率和纤维性振颤低于hand>w^1118+HFD(P<0.05或P<0.01);hand>Nmnat果蝇心脏各指标与hand>Nmnat+HFD相比较未见显著差异(P>0.05);hand>Nmnat+HFD+E果蝇心脏的Nmnat、dFoxo、bmm表达、心脏NAD+水平、SIR2去乙酰化、SOD活力、心脏缩短分数高于hand>Nmnat+HFD(P<0.05或P<0.01),且dFAS和Col4al表达\TAG和MDA水平、心率和纤维性振颤低于hand>Nmnat+HFD(P<0.05或P<0.01)。结论:心脏Nmnat过表达和耐力运动均能抵抗果蝇高脂膳食诱发的心脏脂质过度堆积、氧化损伤、减弱心脏收缩能力和增加纤维性振颤,其分子机制与心脏Nmnat/NAD+/SIR2/dFoxo通路活性增强有关。心脏Nmnat基因过表达联合耐力运动能更好地降低脂毒性心肌症的发生概率,其机制与二者联合对心脏Nmnat/NAD+/SIR2/dFoxo通路活性上调的叠加作用有关。  相似文献   
5.
ABSTRACT

Background: Cycling has gained more attention as an important lifelong physical activity. Learning to cycle independently without assistance is a milestone for most children that requires time and practice to master. Cycling was recently added to the motor development model and so a valid and reliable measure of cycling ability is required to allow accurate assessment of the skill. Cycling has many health benefits along with being a commonly reported physical activity globally and therefore is an important skill to promote in early childhood and throughout life. To date, there are no measurement tools examining the developmental process to independent cycling in the early childhood years. The current study aimed to develop and assess the inter-rater and test-retest reliability of the ‘KIM Cycling Scale’.

Methods: Development of the scale occurred in four phases: (1) development of criteria and stages, which used observation of children when learning to cycle and expert panels to develop the initial developmental stages, (2) review of instructions and criteria and pilot inter-rater and test-retest reliability, to ensure that the scale could be used as a standalone scale without requiring further instructions (3) cycling intervention, which allowed assessment of the developmental nature of children along the scale as they learn to cycle independently and to assess typical and alternate routes to independent cycling and (4) inter-rater and test-retest reliability.

Results: Ninety children took part in phase 1, thirty-six children took part in phase 2, seventy-four children took part in phase 3 and one hundred and forty-nine children took part in phase 4. All three hundred and forty-nine children were between 2 and 6 years. The developed scale included eight stages in total. The scale was found to have excellent inter-rater reliability (ICC?=?0.97, 95% CI?=?0.96–0.98) and good to excellent test-retest reliability [(ICC?=?0.91, 95% CI?=?0.87–0.94) & (ICC?=?0.90, 95% CI?=?0.85–0.93)]. Typical routes to independent cycling along the scale were examined and reported as being step-wise on all occasions except one where a two stage jump was as common as the step-wise route. Alternate routes were also reported.

Conclusion: The current study developed a reliable measurement tool for assessing children between 2 and 6 years of age on the developmental process to independent cycling. Having a cycling scale will allow teachers and practitioners to assess competence in cycling and moreover, track changes in skill development. Furthermore, parents could also use the scale to better understand and better asses their child’s progression when learning to cycle.  相似文献   
6.
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   
7.
Self‐reported measures are an easy, time‐efficient, and low‐cost way to collect research data compared to other assessment methods. They are, however, characterized by several limitations regarding the quality and the clarity of the data they produce, especially when they are implemented in education. The main purpose of the current study was to use a method called discrete choice modeling (DCM) in education, in order to develop a self‐reported instrument that will reduce the bias for socially desirable responses and to assess teachers’ practices in physical activity. DCM method has the ability to overcome the respondents’ tendency to answer in a socially desirable way. A nationally representative sample of 531 Greek early educators participated in this study and were administered a self‐assessment questionnaire based on DCM. Results showed that the DCM based newly developed instrument manages to assess effectively educators’ practices and provided evidence of the applicability of the method in education. Further implications and future recommendations regarding the effective application of DCM in education are discussed.  相似文献   
8.
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   
9.
目的:锻炼与针刺组合对退行性膝关节炎微循环血流灌注量的影响。方法:研究对象40例随机分为2组,分别是针刺组(单纯针刺)和锻炼组(站桩与针刺组合),对其实验前后疼痛程度(VAS)、微循环血流灌注量(MBPU)及皮肤温度的变化进行检测分析。结果:两组实验后,VAS评分明显降低(P<0.01),锻炼组优于针刺组(P<0.05);MBPU降低(P<0.01),锻炼组优于针刺组(P<0.05);局部温度明显提高(P<0.05)。结论:锻炼与针刺组合可以明显缓解退行性膝关节炎的疼痛症状,降低局部微循环血流灌注量,提高皮肤温度;优于单纯针刺疗法。  相似文献   
10.
ABSTRACT

Meta-analytic evidence supports that exercise has benefits for short-term memory (STM) and long-term memory (LTM). However, only three studies with children have tested the differential effects of exercise on STM and LTM. The purpose of this study was to examine the effects of an aerobic fitness test on STM and LTM and to consider the moderating effects of grade level. Children (7–13 years of age) were randomly assigned to either perform an aerobic fitness test before (exercise prior) or after (exercise post) performing the Rey Auditory Verbal Learning Test (RAVLT) to assess memory. Memory was tested again after approximately 24 hours. There were significant differences in memory performance as a function of grade with 4th and 6th graders consistently outperforming 2nd graders. For learning, Day 1 Retention, 24-hr recall, and Day 2 Retention, the exercise prior group performed better than the exercise post group. It is concluded that an aerobic fitness test performed prior to a declarative memory test benefits LTM as compared to when the aerobic fitness test is performed after the memory test.  相似文献   
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