Time-restricted feeding in young men performing resistance training: A randomized controlled trial†

A randomized controlled trial was conducted to examine eight weeks of resistance training (RT) with and without time-restricted feeding (TRF) in order to assess nutrient intake and changes in body composition and muscular strength in young recreationally active males. The TRF programme consisted of consuming all calories within a four-hour period of time for four days per week, but included no limitations on quantities or types of foods consumed. The RT programme was performed three days per week and consisted of alternating upper and lower body workouts. For each exercise, four sets leading to muscular failure between 8 and 12 repetitions were employed. Research visits were conducted at baseline, four, and eight weeks after study commencement. Measurements of total body composition by dual-energy X-ray absorptiometry and muscle cross-sectional area by ultrasound were obtained. Upper and lower body strength and endurance were assessed, and four-day dietary records were collected. TRF reduced energy intake by ～650?kcal per day of TRF, but did not affect total body composition within the duration of the study. Cross-sectional area of the biceps brachii and rectus femoris increased in both groups. Effect size data indicate a gain in lean soft tissue in the group that performed RT without TRF (+2.3?kg, d?=?0.25). Upper and lower body strength and lower body muscular endurance increased in both groups, but effect sizes demonstrate greater improvements in the TRF group. Overall, TRF reduced energy intake and did not adversely affect lean mass retention or muscular improvements with short-term RT in young males.     

Metabolic time-course response after resistance exercise: A metabolomics approach

This study analysed the time course of the global metabolic acute response after resistance exercise (RE), with the use of proton nuclear magnetic resonance (¹H NMR) spectroscopy. Ten young healthy males performed 4 sets of 10 repetitions at 70% of one-repetition maximum in the leg press and knee extension exercises and had the serum metabolome assessed at 5, 15, 30 and 60 min post-RE. Measurements were also performed 1 h earlier and immediately before the exercises, as an attempt to characterise each participant’s serum metabolome at rest. One-way ANOVA was applied and the significance level was set at P ≤ 0.05. RE promoted an increase in 2-hydroxybutyrate, 2-oxoisocaproate, 3-hydroxyisobutyrate, alanine, hypoxanthine, lactate, pyruvate and succinate concentrations. However, isoleucine, leucine, lysine, ornithine and valine had their concentrations decreased post-RE compared with at rest. This is the first study to show significant changes in serum concentration of metabolites such as 2-oxoisocaproate, 2-hydroxybutyrate, 3-hydroxyisobutyrate, lysine, hypoxanthine and pyruvate post-RE, attesting metabolomics as an interesting approach to advance in the understanding of global RE-induced metabolic changes. Moreover, the present data could influence the time point of blood collection in the future studies that aims to investigate metabolism and exercise.     

论行政权力公开运行的动力、阻力和发展趋势

政府权力属于公共权力.我国政府公开虽有多种提法,但实质强调的都是政府公共权力运行的公开.行政权力公开是核心内容,有着明确的反腐倡廉的指向性.公共权力即行政权力公开运行虽然已取得了显著的成就,但要继续深入开展就必须对政府公开的动力和可能遇到的阻力进行科学的分析,并采取增动力破阻力的有效措施,建立起长效机制,这是行政权力公开运行的发展趋势,也是当前面临的紧迫任务.     

《清代学者象传》的生成与传播

《清代学者象传》是中国国家博物馆馆藏书画特色藏品,记录了清代主要学者肖像及传记,是了解清代学者形象的重要文献.关于这套画册的缘起与生成、选录与编纂的标准、画成之后的刊印和发行、传播与影响等,在学术界未能引起足够的关注.本文即在梳理时人与后人文献的基础上,尽可能厘清叶衍兰、叶恭绰等人编著《清代学者象传》的来龙去脉.《清代...     

冰上课中运用抗阻训练的实验研究

抗阻训练作为全面身体锻炼的重要方法,可以显著增长肌肉力量和体积,其在改善肌肉速度、平衡性、协调性、弹跳力、柔韧性等方面的素质效果明显。采用文献资料法及实验对比法,对抗阻训练的原理、抗阻训练的超量恢复、抗阻训练的交叉迁移、抗阻训练方案设计以及教学要求方面进行分析并进行了实验研究。实验结果显示：在冰上教学中运用抗阻训练能明显增加学生的体能储备,提高学生速滑技术水平;改变差生的弱势心理倾向,增强学习信心,从而提高了冰上课教学效果。     

中国赛艇队男轻运动员身体成分监测对训练效果的研究

通过国家赛艇队4名男轻队员冬训前后身体成分变化的研究,分析探讨中国赛艇男轻运动员最佳身体成分。结果显示,一定范围内体脂％的下降与赛艇轻量级运动员有氧耐力的提高显著相关;赛艇轻量级运动员瘦体质量的增加与否可反映力量训练的效果;本研究中,男子轻量级运动员身体成分的改变与专项测功仪能力的变化未呈显著相关性。     

Roller ski rolling resistance and its effects on elite athletes’ performance

Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical fitness in a laboratory environment whilst performing classical and freestyle (skating) techniques on roller skis. For elite athletes, the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance in order to allow the correct comparison between the results of different test occasions. In this study, the roller skis’ rolling resistance was measured on the ski-treadmill’s surface using a roller ski rolling resistance measurement system specially produced for this purpose. The study investigated the influence of significant changes in rolling resistance on physiological variables. The results showed that during submaximal exercise, power, oxygen uptake, heart rate and blood lactate were significantly changed by different rolling resistances, while there were no significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed by different rolling resistances and this occurred without significant changes in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion were insignificant or small.     

一种画等效电路的有效办法

求复杂的混联电路的等效电阻,常常是解决电路计算问题的关键,而得出复杂的混联电路的等效电路,是求得等效电阻的必径之路,本介绍一种画等效电路的有效方法。     

间壁式传热过程中的热阻计算

通过对管道设备保温及管壳式换热器传热过程各热阻的估计分析,提出了简化计算间壁式传热过程的方法.     

小麦灌浆期叶片游离脯氨酸和可溶性蛋白质含量与抗旱性的关系

土壤干旱时 ,小麦灌浆期叶片游离脯氨酸含量增加 ,可溶性蛋白质含量减少 .抗旱性强的品种脯氨酸含量上升的幅度小于抗旱性弱的品种 ,且差异显著 ;抗旱性强的品种可溶性蛋白质含量下降的幅度小于抗旱性弱的品种