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151.
褪黑素(melatonin,MT)在同步昼夜节律方面具有关键作用,且抑郁症的主要特征就是昼夜节律紊乱导致的睡眠障碍和褪黑素分泌紊乱。针对昼夜节律系统开发出的褪黑素类似物(如阿戈美拉汀、雷美替胺、他司美琼等)在治疗抑郁症方面有积极作用,特别是阿戈美拉汀,这是一种具有抗抑郁和抗焦虑作用的褪黑素受体激动剂及5-HT2C受体拮抗剂。研究综述了昼夜节律紊乱与抑郁症之间的关联,以及褪黑素在运动调控生物节律与改善抑郁行为方面的作用及机制,并提出了运动联合MT的抗抑郁策略。提出运动的抗抑郁作用,一方面通过MT的分泌调节使生物节律同步和MT促进海马神经发生和生物钟基因表达同步,另一方面通过MT调节脑源性神经营养因子节律和水平及改善炎症和氧化应激。  相似文献   
152.
ABSTRACT

The length of telomeres is an objective measure of biologic ageing. This study evaluated the extent minutes of walking per week are associated with leukocyte telomere length (LTL) in a random sample of 5,823 U.S. adults. The investigation was cross-sectional and data were obtained from the National Health and Nutrition Examination Survey (NHANES). LTL was measured by the quantitative polymerase chain reaction method. Walking minutes was calculated from walking frequency and duration measures. Results showed that for each year of chronological age, telomeres were 15.6 base pairs shorter (P < 0.0001). With walking minutes and LTL treated as continuous variables, the relationship was quadratic, not linear (F = 11.2, P = 0.0023). With walking time divided into three categories, adults who performed ≥ 150 minutes of walking per week had longer telomeres than those who did no regular walking, and those who did some, but less than the recommendation (F = 5.0, P = 0.0137). Regular walkers were estimated to have a biologic ageing advantage associated with 6.5–7.6 years less biologic ageing compared to non-walkers, after adjusting for covariates. Additional investigations designed to study causality and the mechanisms associated with the walking and LTL relationship are needed.  相似文献   
153.
以健康行动过程取向理论为理论背景,对644名在校大学生进行教育干预实验研究.干预措施包括课堂和课下指导、微信等即时通信工具宣传、发放健康行为宣传册等,干预时间为10周.在干预前后共进行了两次问卷调查、三次身体素质测试.结果:①根据HAPA阶段划分,大学生大部分处于健康锻炼行为无意向和意向阶段,仅有14.1%处于行动阶段;②干预对大学生锻炼行为意向水平和体育锻炼等级具有积极影响;③干预对大学生身体素质整体水平有积极影响;④锻炼自我效能作为社会认知变量在健康行为过程取向理论的各个阶段都发挥重要作用.建议通过提高个体锻炼自我效能感和制订合适的锻炼计划增加大学生中参加有规律的体育锻炼人数比例.  相似文献   
154.
研究目的:运用元分析法( Meta-analysis)检验有氧运动对我国肥胖少年儿童的干预效果。研究方法:检索20052010年23篇相关文献进行元分析,对23篇文献质量进行评估后,采用随机效应模型对研究的效应值和异质性进行检验。研究结果:23篇文献GRADE风险评估结果为A级12篇、B级9篇、C级2篇,文献存在系统误差的可能性很低。元分析结果中效应值为2.59,95%CI(2.14,3.05),说明有氧运动干预对于我国少年儿童的肥胖具有很好的干预效果。异质性检验指标Q值为21.13(P=0.51),I2=0%,研究间不存在异质性和发表偏倚。研究结论:有氧运动是我国肥胖少年儿童进行减肥的有效手段,对少年儿童的肥胖干预效果十分明显。持续3个月以上,每周36次,每次4090分钟的中等强度有氧运动对于我国少年儿童减肥效果最佳。  相似文献   
155.
针对学生做了大量习题但收效却不大这种教学中常见的现象,分析了原因,并指出教师要通过引导学生“一题十想”,明晰解题思路,总结解题规律,实现习题效能的最大化。  相似文献   
156.
The aim of this article was to understand how active power is used in squat and countermovement jumps. A simple empirical model comprising a mass, a spring, an active element and a damper, together with an optimisation principle, was used to identify the mechanical factors that maximise performance of jumps without countermovement (squat jumps, SJ) and with countermovement (CMJ). Twelve amateur volleyball players performed SJ from two initial positions and CMJ with two degrees of counterbalancing, while kinematic data were collected (jump height, push-off duration and position of the centre of mass). The model adjusted well to real data of SJ through all the impulse phase, and slightly less adequately at the end of this phase for CMJ. Nevertheless, it provides a satisfactory explanation for the generation and utilisation of active power for both type of jumps. On average, the estimated power of the active elements, the spring, and the damper were greater in the SJ. Based upon the result obtained with this model, we suggest that active power is best evaluated with SJ. The reason for this is that, during this kind of jump, the elements associated with the damper consume much of the energy produced by the active elements. The participation of the elements that consume the energy generated by the active elements is less in CMJ than in SJ, allowing for a better utilisation of this energy. In this way it is possible to achieve a better performance in CMJ with less active power.  相似文献   
157.
Purpose: In a cross-sectional study design, we evaluated the resting heart rate (HRbaseline) and exercise and postexercise stress test-related chronotropic responses in male practitioners of recreational ballroom dancing (BD; n = 25, Mage = 26.6 ± 6.1 years) compared to a control group of insufficiently active nondancers (CG; n = 25, Mage = 25.9 ± 4.5 years). Method: All participants underwent a submaximal exercise test. At 85% of the maximal predicted HR, the recovery protocol was started, and heart rate recovery (HRR) was recorded during 1-min intervals for 5 min. Results: Compared with CG, BD showed lower HRbaseline (70 beats per minute [bpm] vs. 62 bpm, respectively, U = 143, p < .05, ES = .46), lower preexercise HR (94 bpm vs. 86 bpm, U = 157, p < .05, ES = .42), longer exercise test duration (346 s vs. 420 s, U = 95.5, p < .05, ES = .59), and higher HRR for 5 min postexercise (U = 1.29–1.89, p < .05, ES = .33–.50) as follows: 1st min (32 bpm vs. 40 bpm), 2nd min (45 bpm vs. 53 bpm), 3rd min (51 bpm vs. 58 bpm), 4th min (55 bpm vs. 59 bpm), and 5th min (59 bpm vs. 63 bpm). The coefficient of HRR from the 1st min to the 5th min postexercise was similar in both groups (U = 229–311, p > .05, ES = < .10–.22). Conclusion: Heightened cardiovascular functional status characterized by favorable enhanced chronotropic dynamics appears to occur in practitioners of recreational ballroom dancing, which suggests that this modality of exercise may result in health benefits.  相似文献   
158.
摘要:目的:Nrf2是机体氧化还原平衡的主要调节因子,本研究试图探讨Nrf2在有氧运动训练中对小鼠骨骼肌抗氧化能力的作用。方法:8周龄野生C57BL/6J小鼠和Nrf2敲除小鼠40只,雌雄各半。进一步各为安静组和运动组,每组10只,共4组:分别为野生安静组(WC),野生运动组(WE),敲除安静组(KC)和敲除运动组(KE)。运动组进行4周运动强度为70%VO2max跑速的跑台运动,每周运动6 d,每天运动1 h。运动组最后一次运动后休息48 h脱颈处死,取小鼠后腿骨骼肌。RT-PCR测量Nrf2及Nrf2介导的抗氧化基因mRNA表达量;Western blot法测定骨骼肌Nrf2及抗氧化蛋白含量; GSH试剂盒测量GSH/GSSG比值。结果:1)在安静情况下,KC组和WC组相比,骨骼肌中GSR、NQO1、GCLc、GPX、HO-1和SOD2这6个抗氧化蛋白表达以及GSH/GSSG值没有显著性改变。 2)4周有氧运动训练之后,Nrf2敲除运动组的大部分抗氧化蛋白(CAT, NQO1-1, GCLc, HO-1 and SOD2)和GSH/GSSG值都要显著低于野生运动组。结论:4周70%VO2max强度的有氧运动训练,增加了成年Nrf2敲除和野生鼠骨骼肌抗氧化蛋白表达量和GSH/GSSG比值的差异,而在无训练安静情况下在两种鼠中这些指标的差异不大。说明Nrf2对有氧运动训练中骨骼肌的抗氧化反应起着非常重要的作用。  相似文献   
159.
Huan Xiong 《Sport in Society》2019,22(8):1415-1432
Abstract

By applying feminist geographical theories and qualitative research methods, this article reveals Chinese women’s exercise experiences in urban spaces and discusses how women, through physical activity in neighbourhoods, public places and commercial facilities, constructed social spaces of their own. The findings show that exercise spaces are potentially sites for women’s health, well-being, social networking and collective empowerment. They challenge traditional gendered urban spaces by deconstructing the dual structure of ‘public’ and ‘private’ spheres, inducing women to gradually shift from the ‘edge’ to the ‘centre’. Though the spatial differences in women’s physical activities reflect the diversity and dynamics of women’s spatialities, they also imply the continuous social powers on women in exercise fields, where gendered disparities and class stratification may be sustained.  相似文献   
160.
摘要:心血管疾病(CVD)一直是全世界最主要的死因。由于CVD等慢性疾病对健康的威胁越来越大,有必要开展生活方式干预项目以控制这些疾病的危险因素。本研究的目的是评估美国的重要慢病干预项目—HELPS治疗型生活方式改变(TLC)项目对减少CVD危险因素和其他慢性疾病的有效性。方法:140位大学教职工参加为期12周的HELPS TLC项目,干预前后用配对t检验对其体重、BMI、腰围(WC)、6分钟步行距离(6MWD)、空腹血脂和血糖进行测定和比较。结果:干预后6MWD显著增加,总胆固醇(TC)和WC显著下降。对“高危”参与者进一步分析显示:BMI(-1.5±0.5,-3.9%)、TC(- 22.8±4.0,-9.0%)、LDL(- 14.1±4.9,9.3%)和血糖(-6.9±2.2,-6.1%)均显著下降;男性腰围(-4.5±0.8,-10%)显著减小,女性未见显著改变(-1.5±0.5,-4.0%)。此外,体重的变化与TC(r=0.43)、LDL(r=0.35)和血糖(r=0.44)的变化均显著相关。结论:参加12周的生活方式干预项目可以使CVD危险因素减少,特别是在CVD“高危”个体中。HELPS TLC项目的远期效果还待进一步深入研究。  相似文献   
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