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991.
理论和实践表明,要克服农村金融领域的市场失灵,离不开政府的支持。近年来,我国各级政府在建立和完善农村金融风险补偿机制、健全政策性农业保险制度以及实现农业信贷与保险有机对接等方面进行了卓有成效的改革探索。今后,不但要注重农业已存在的不同金融需求,更应大力打造不同类型的金融生态,规范发展地方性农村金融机构,扩大农村金融供给,激活、满足农村金融需求;同时,要发挥财政、信贷资金相互协调的配套作用,并建立完善农村征信体系。  相似文献   
992.
High Intensity Interval Training (HIIT) can be performed with different effort to rest time-configurations, and this can largely influence training responses. The purpose of the study was to compare the acute physiological responses of two HIIT and one moderate intensity continuous training (MICT) protocol in young men. A randomised cross-over study with 10 men [age, 28.3?±?5.5years; weight, 77.3?±?9.3?kg; height, 1.8?±?0.1?m; peak oxygen consumption (VO2peak), 44?±?11?mL.kg?1.min?1]. Participants performed a cardiorespiratory test on a treadmill to assess VO2peak, velocity associated with VO2peak (vVO2peak), peak heart rate (HRpeak) and perceived exertion (RPE). Then participants performed three protocols equated by distance: Short HIIT (29 bouts of 30s at vVO2peak, interspersed by 30s of passive recovery, 29?min in total), Long HIIT (3 bouts of 4?min at 90% of vVO2peak, interspersed by 3?min of recovery at 60% of vVO2peak, 21?min in total) and MICT (21?min at 70% of vVO2peak). The protocols were performed in a randomised order with ≥48 h between them. VO2, HRpeak and RPE were compared. VO2peak in Long HIIT was significantly higher than Short HIIT and MICT (43?±?11 vs 32?±?8 and 37?±?8?mL.kg?1.min?1, respectively, P?P?P?2, HR and RPE than Short HIIT and MICT, suggesting a higher demand on the cardiorespiratory system. Short HIIT and MICT presented similar physiologic and perceptual responses, despite Short HIIT being performed at higher velocities.  相似文献   
993.
β-hydroxy-β-methylbutyrate (calcium: HMB-Ca and free acid: HMB-FA) and α-hydroxyisocaproic acid (α-HICA) are leucine metabolites that have been proposed to improve body composition and strength when combined with resistance exercise training (RET). In this double-blind randomized controlled pragmatic trial, we evaluated the effects of off-the-shelf supplements: α-HICA, HMB-FA and HMB-Ca, on RET-induced changes in body composition and performance. Forty men were blocked randomized to receive α-HICA (n?=?10, fat-free mass [FFM]?=?62.0?±?7.1?kg), HMB-FA (n?=?11, FFM?=?62.7?±?10.5?kg), HMB-Ca (n?=?9, FFM?=?65.6?±?10.1?kg) or placebo (PLA; n?=?10, FFM?=?64.2?±?5.7?kg). The training protocol consisted of a whole-body resistance training routine, thrice weekly for 8 weeks. Body composition was assessed by dual-energy x-ray absorptiometry (DXA) and total body water (TBW) by whole-body bioimpedance spectroscopy (BIS), both at baseline and at the end of weeks 4 and 8. Time-dependent changes were observed for increase in trunk FFM (p?相似文献   
994.
This study aimed to determine the suitability of the load-velocity relationship to prescribe the relative load (%1RM) in women, as well as to compare the load-velocity profile between sexes and participants with different strength levels. The load-velocity relationship of 14 men (1RM: 1.17 ± 0.19) and 14 women (1RM: 0.66 ± 0.13) were evaluated in the bench press exercise. The main findings revealed that: (I) the load-velocity relationship was always strong and linear (R2 range: 0.987–0.993), (II) a steeper load-velocity profile was observed in men compared to women (Effect size [ES]: 1.09), with men showing higher velocities for light loads (ES: ? 0.81 and ? 0.40 for the y-intercept and 30%1RM, respectively), but women reporting higher velocities for the heavy loads (ES: 1.14 and 1.50 at 90%1RM and 100%1RM, respectively); and (III) while the slope of the load-velocity profile was moderately steeper for weak men compared to their strong counterpart (ES: 1.02), small differences were observed between strong and weak women (ES: ? 0.39). While these results support the use of the individual load-velocity relationship to prescribe the %1RM in the bench press exercise for women, they also highlight the large disparities in their load-velocity profile compared to men.  相似文献   
995.
研究旨在探讨一次不同抗阻训练方案对外周血CD4+和CD8+T淋巴细胞亚群迁移和凋亡的影响。通过实验法15名无训练经历的健康青年男性分别进行一次以促进肌肉肥大(H-RT组,方案:70%1RM,10RM,3组,组间间歇1.5 min)和以改善肌肉耐力(E-RT组,方案:60%1RM,15RM,3组,组间间歇1 min)为目的的抗阻训练方案。并于训练前、训练后即刻、训练后2 h和24 h利用流式细胞仪测定表面标志物CX3CR1和annexin V表达量检测CD4+、CD8+T淋巴细胞亚群迁移和凋亡(用阳性表达率表示)。得出以下数据:(1)CD4+T细胞在H-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率显著性升高(P<0.05)。E-RT组annexin V阳性表达率在运动后即刻降低(P<0.05),24 h显著性升高(P<0.05);CX3CR1阳性表达率仅在运动后即刻升高(P<0.05)。(2)CD8+T细胞在H-RT组和E-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率均显著性升高(P<0.05)。通过对以上数据的分析,研究得出以下结论:CD4+T淋巴细胞亚群对于急性抗阻训练的免疫反应存在运动方案依赖性。  相似文献   
996.
This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R2 values of >0.85 for all variables excluding deadlift mean velocity (R2 = 0.54–0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6–8.8%) were found for all variables, with SWC ranging 1.7–7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance.  相似文献   
997.
This study aimed to evaluate the effect of simulated training strategies on performance potential in elite short-track speed skaters. Training load and field-based criterion performances from fifteen athletes (10 males, 5 females) were collected over a 3-month training period and the relationship between training loads and performance was computed with a variable dose-response model using a genetic algorithm. Individual simulations of tapers preceded or not preceded by an overload training (OT) were assessed. We obtained a significant correlation between actual and modelled performances (R2 = 0.76 ± 0.07). Regarding model parameters, no significant difference was found between males and females but the time to recover performance tended to be lower in females. Simulations in which the taper parameters were free highlighted that an exponential or a step taper were the most effective for increasing performance compared to a linear taper (p < 0.05). Optimal exponential taper duration after OT was 10.7 ± 2.4d and the optimal load reduction was 75.9 ± 3.7%. OT intensity had the greatest influence on the predicted performance, followed by OT duration, taper decay, and to a lesser extent load reduction during taper and taper duration. Thus, a variable dose-response systems model allows the evaluation of different taper strategies and their potential effect on performance changes.  相似文献   
998.
以我国草根组织中的典型组织——跑团为例,分析了我国跑团兴起的主要原因,发展过程中存在的问题:跑团内部机制不健全,治理方式滞后;缺乏稳定的社会资源;政府职能部门引导、扶持不力;相关的规章制度、法律不够完善;较难获得合法身份致使发展受阻,缺少主管单位监督和行业自律;跑团存在多种安全隐患;对于各种跑团社交软件及社交平台的管理不够。据此提出了对策:对跑团进行分级分类管理,充分发挥中国田协的指导与监督作用,政府部门不断完善跑步公共服务体系,加强跑团制度建设与规范管理,健全安全健康监管保障体系。  相似文献   
999.
目的:比较两种大强度间歇训练手段对优秀自行车运动员有氧运动能力的影响。方法:将15名备战全国“十三运”的云南省自行车队男子运动员随机分为3组, S组训练方案采用SIT/耐力训练, H组训练方案采用HIIT/耐力训练, C组为对照组,进行传统耐力性训练;训练持续3周。训练前后进行递增负荷测试和有氧运动能力测试,测试指标包括最大摄氧量绝对值(VO2max)、最大摄氧量相对值(VO2max/kg)、每分通气量(VE)、最大心率(HRmax),并通过公式计算每搏输出量(SV),以及测试递增负荷后即刻血乳酸(BLA)、最大有氧功率(P)和40 km个人计时成绩进行了测试。结果:(1)3周训练后,S组运动员VE、HRmax、SV、VO2max、VO2max/kg、P和ITT40km均较训练前有显著性提高(P<0.05);H组运动员VE、VO2max/kg、ITT40km较训练前有显著性增加(P<0.05),BLA有显著性的下降(P<0.05)。(2)S组运动员ΔVE、ΔHRmax、ΔSV、ΔVO2max、ΔVO2max/kg、ΔBLA、ΔITT40km显著提升(P<0.05),且优于其余两组;H组仅ΔITT40km存在明显提升(P<0.05)。结论:间歇训练结合耐力训练对优秀公路自行车运动员的呼吸系统、有氧供能系统可产生积极的影响;而且,SIT结合耐力训练较HIIT结合耐力训练或传统耐力训练更能提高公路自行车运动员的有氧代谢能力和有氧运动能力,训练效果更佳。  相似文献   
1000.
根据协同理论和机制设计理论,遵循动态性、务本性和创新性等原则,设计京津冀体育传统项目学校协同发展联动机制,据此进行案例设计与分析,旨在促进京津冀体育传统项目学校的协同、可持续发展。研究表明:①京津冀体育传统项目学校协同发展联动机制行为人包括京津冀体育传统项目学校协同发展委员会、京津冀体育传统项目学校协同发展小组和京津冀区域各体育传统项目学校,各司其职,履行各自的权利与义务;②其功能包括激励、制约和保障功能,三者相互作用、相互制约;③其形式与载体包括涉及激励标准和经费奖励的激励政策措施,涉及制度、程序和权利等的制约政策措施,涉及经费、师资和场馆的保障政策措施;④依据联动机制设计京津冀体育传统项目学校系列赛事和夏令营活动是促进协同发展的有效手段和途径。  相似文献   
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