谈健美操的创编和音乐选配

动作组成是健美操的基础,音乐是健美操的灵魂,本文从创编的任务,创编的侧重点,以及创编的音乐选择,谈了笔者的几点看法。     

Double-edged sword: The effect of exergaming on other forms of exercise; a randomized controlled trial using the self-categorization theory

BackgroundNo study has yet adopted the perspective of the self-categorization theory to examine the impact of playing exergames on players' attitudes and intentions towards other forms of exercise.PurposeTo examine the impact of playing exergames on players' attitudes and intentions to engage in other exercise and how such an impact depends on previous exercise frequency.MethodsThis randomized controlled trial recruited 117 college students who were randomly assigned to either an intervention group (n = 55) or a control group (n = 62). Participants in the first group played an exergame for 30 min, three times per week for 12 weeks. This study calculated the changes in the participants' attitudes and intentions before and after the program, and compared the differences between the two groups.ResultsExergaming improved the players' attitudes toward other forms of exercise. Such improvement was significant for frequent exercisers, but not for infrequent exercisers. Surprisingly, playing exergames strengthened the intentions to engage in other forms of exercise for frequent exercisers, but weakened such intentions for infrequent exercisers.ConclusionsExergaming encourages frequent exercisers to engage in other forms of exercise, but does the opposite among infrequent exercisers.OriginalityThis study is the first identifying the contingent effect of exergaming on users' attitudes and intentions toward other forms of exercise.     

Ion distribution and protein proteolysis affect water holding capacity of Longissimus thoracis et lumborum in meat of lamb subjected to antemortem exercise

Exercise has been shown previously to reduce the water holding capacity (WHC) of meat in lamb. The consequence of changes in the distribution of ions pre- and post-rigor and proteolysis on WHC is relatively unknown. Twelve crossbred lambs were used to investigate the effect of exercise on the meat quality traits of the Longissimus thoracis et lumborum (LTL) muscle. There were no treatment effects on Warner-Bratzler shear force (WBSF), myofibril and sarcoplasmic protein solubility, denaturation or sarcomere length. With exercise the initial pH of the muscle was lower and the rate of pH fall to rigor was faster compared to controls. Exercise caused increased purge and meat fluid had a lower osmolarity, magnesium, potassium and sodium concentration. Proteolysis of desmin occurred after day 3 and vinculin on day 7 of ageing with exercise. It was concluded that exercise caused changes in the distribution of ions and the proteolysis of muscle proteins that reduced the ability of the muscle to bind or hold water.     

Physical activity-induced alterations on tissue lipid composition and lipid metabolism in fattening pigs

In a first experiment one group of pigs was maintained in free-range conditions according to the traditional way in a Mediterranean forest (exercised-1) and another group was housed individually and received acorns (sedentary-1). In a second experiment two groups of pigs were fed a mixed diet for the whole experimental period. One of these groups was housed individually in 8 m² pens (sedentary-2). The other group was housed in a corridor and forced to walk daily (exercised-2).The subcutaneous fat and neutral lipids of muscle from the exercised pigs fed acorns had higher C18:1n-9, MUFA, C18:1/C18:0, MUFA/SAT and lower C16:0 and SAT when compared with the fat from the pigs fed acorns in confinement. Those exercised animals fed the mixed diet had also lower C16:0 and SAT in subcutaneous fat and lower SAT and higher C18:2, C18:3, PUFA and MUFA/SAT in neutral lipids when compared with the sedentary pigs, which may indicate that delta-9-desaturase activity was higher in exercised than in sedentary pigs. Exercised pigs had higher acid and neutral esterases and lower neutral lipase activity than sedentary pigs. No differences in the α-tocopherol concentration and TBARS values of meat samples among the pigs that received a mixed diet either exercised or sedentary were observed. The moderate exercise reduced the postprandrial concentrations of triglycerides in plasma, but did not reduce other plasma levels.     

Adaptations of Skeletal Muscle Mitochondria to Obesity,Exercise, and Polyunsaturated Fatty Acids

Mitochondria intricately modulate their energy production through the control of mitochondrial adaptation (mitochondrial biogenesis, fusion, and/or fission) to meet energy demands. Nutrient overload may result in dysregulated mitochondrial biogenesis, morphology toward mitochondrial fragmentation, and oxidative stress in the skeletal muscle. In addition, physical activity and diet components influence mitochondrial function. Exercise may stimulate mitochondrial biogenesis and promote mitochondrial fusion/fission in the skeletal muscle. Moreover, some dietary fatty acids, such as n‐3 polyunsaturated fatty acids and conjugated linoleic acid, have been identified to positively regulate mitochondrial adaptation in the skeletal muscle. This review discusses the association of mitochondrial impairments and obesity, and presents an overview of various mechanisms of which exercise training and mitochondrial nutrients promote mitochondrial function in the skeletal muscle.     

Accurate work-rate measurements during in vivo MRS studies of exercising human quadriceps

INTRODUCTION: Given that we have reached a point in the field of muscle energetics where absolute measurements are warranted to take the area forward, we designed an ergometer, including two force and two displacement transducers, allowing dynamic and isometric knee extension within a MR system and accurate measurements of power output. METHODS: On the basis of repeated measurements, the force and displacement transducers accuracy was 1% for values ranging from 0 to 394 N and 4% for values ranging from 0 to 20 cm. In addition, measurements were not affected by magnetic field. MRS experiments in exercising muscle were conducted in eight subjects. They performed two standardized dynamic alternate leg extension exercises (25 and 35% of MVC) while the corresponding metabolic changes were measured using (31)P-MRS. RESULTS: The mean power output produced during both exercises were 63 +/- 16 and 81 +/- 15 W while the eccentric work was reduced i.e. 12 +/- 14 and 21 +/- 6 W for the moderate and heavy exercise respectively. The corresponding metabolic changes were significant with a 20-40% PCr depletion and an end of exercise pH ranging from 0.02 to 0.70 pH units. CONCLUSION: Overall, the present ergometer allows quadriceps exercise in a MR system and should be useful for future metabolic studies for which reliable and absolute quantification of power output is warranted.     

Physical activity levels among adult computer users

As computer use becomes prevalent at work and in leisure pursuits it presents a potential barrier to regular physical activity. However an individual’s confidence in overcoming such barriers may moderate the relationship between computer use and physical activity levels. This study examined the associations among computer use, self-efficacy in overcoming barriers to exercise, and physical activity levels among adult computer users. Participants (N = 615) were recruited through national email and newsletters announcements, and completed standardized self-report questionnaires online. Computer use was not associated with meeting physical activity guidelines (adjusted odds ratio, AOR = 0.63-1.00, n.s.). Among leisure computer users, the moderate efficacy group (AOR = 3.72, 95% CI = 1.59-8.69) and the high efficacy group (AOR = 5.31, 95% CI = 2.37-11.91) had higher odds of meeting physical activity guidelines compared to the low efficacy group. Among the work related computer users, the high efficacy group (AOR = 2.83, 95% CI = 1.18-6.77) had higher odds of meeting physical activity guidelines than the low efficacy group. These results suggest that barriers posed by high levels of computer use are surmountable. Efforts to increase efficacy in overcoming barriers to exercise may be more practical and have a greater impact on physical activity levels than trying to decrease computer use among adults.     

Blackboard平台在《企业行为模拟—沙盘推演与ERP应用》课程中的应用

本文概括了跨专业实验课程《企业行为模拟——沙盘推演与ERP应用》的特点,并介绍了blackboard平台在该课程教学中的应用,包括提供了个性化学习的内容支持、团队协作学习支持、信息发布的支持、师生交流支持等各方面的内容。     

工程制图教学质量的提高

为了在有限的学时内让学生更好地掌握工程制图知识,提出了从多媒体教学、模型引入、习题与讲解、因材施教等方面提高教学质量的方法.经实践证明,这种改革达到了良好的教学效果.