首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   16篇
  免费   0篇
教育   5篇
科学研究   1篇
体育   10篇
  2020年   1篇
  2017年   2篇
  2013年   6篇
  2012年   1篇
  2011年   1篇
  2008年   1篇
  2007年   1篇
  2006年   1篇
  2004年   1篇
  1985年   1篇
排序方式: 共有16条查询结果,搜索用时 15 毫秒
1.
本文利用专家访谈法、文献资料法等方法对影响大学生休闲体育活动的因素做出了归纳,然后在采用问卷调查法以上海市高校大学生为调查对象,调查大学生关于休闲体育的现状及意识,得出影响与阻碍大学生休闲体育活动的内部因素和外部因素之间的相互关系.  相似文献   
2.
Abstract

Ghrelin is a hormone that stimulates hunger. Intense exercise has been shown to temporarily suppress hunger after exercise. In the present study, we investigated whether post-exercise hunger suppression is mediated by reduced plasma total ghrelin concentrations. Nine men and nine women participated in the study. Their mean physical characteristics were as follows: age 24.8 (s x  = 0.9) years, body mass index 22.9 (s x  = 0.6) kg · m?2, maximal oxygen uptake ([Vdot]O2max) 57.7 (s x  = 2.2) ml · kg?1 · min?1. The participants completed two 3-h trials (exercise and control) on separate days in a randomized balanced design after overnight fasts. The exercise trial involved a 1-h treadmill run at 73.5% of [Vdot]O2max followed by 2 h of rest. The control trial consisted of 3 h of rest. Blood samples were collected at 0, 0.5, 1, 1.5, 2, and 3 h. Total ghrelin concentrations were determined from plasma. Hunger was assessed following blood sampling using a 15-point scale. The data were analysed using repeated-measures analysis of variance. Hunger scores were lower in the exercise trial than in the control trial (trial, P = 0.009; time, P < 0.001; trial × time, P < 0.001). Plasma total ghrelin concentrations did not differ between trials. These findings indicate that treadmill running suppresses hunger but this effect is not mediated by changes in plasma total ghrelin concentration.  相似文献   
3.
The use of diagrams in learning and communication is generally considered efficacious and an important skill to cultivate, especially among science students. At the same time, previous research has revealed many problems in student diagram use, including a lack of spontaneity in such use, but the extent to which these problems persist into the tertiary level had not been investigated. The present study examined science and engineering university students’ use of diagrams in note taking to learn information from a written passage, and in a subsequent task of constructing an explanation of that information for another person. The results showed that the students used significantly fewer diagrams in explaining compared to when they were note taking, suggesting that many students may lack awareness of the usefulness of diagrams in effectively communicating information to others. The results also revealed that the students used significantly more diagrams in taking notes from and explaining a passage with higher imageability (i.e. easier to visually imagine) compared to one with lower imageability. Educational implications of the findings are discussed.  相似文献   
4.
The purpose of this study was to propose an optimization procedure for determining power output during very brief maximal pedalling exercise. Twenty-six healthy male students (21-28 years) performed anaerobic tests on a Monark bicycle ergometer with maximal effort for less than 10 s at eight different loads ranging from 28.1 to 84.2 Nm in pedalling moment. The maximal pedalling rate was determined from the minimal time required for one rotation of the cycle wheel. Pedalling rate decreased linearly with the load. The relationship between load and pedalling rate was represented by two linear regression equations for each subject; one regression equation was determined from eight pairs of pedalling rates and loads (r less than -0.976) and the other from three pairs (at 28.1, 46.8, 65.5 Nm; r less than -0.969). The two regression coefficients of the respective regression equations were almost identical. Mean +/- S.D. of maximal power output (Pmax) which was determined for each subject based on the two linear regression equations for eight pairs and three pairs of pedalling rates and loads was 930 +/- 187 W (13.4 +/- 1.6 W kgBW-1) and 927 +/- 187 W (13.4 +/- 1.6 W kgBW-1), respectively. There was no statistically significant difference between the values of Pmax which were obtained from each equation. It was concluded that maximal anaerobic power could be simply determined by performing maximal cycling exercise at three different loads.  相似文献   
5.
Ghrelin is a hormone that stimulates hunger. Intense exercise has been shown to temporarily suppress hunger after exercise. In the present study, we investigated whether post-exercise hunger suppression is mediated by reduced plasma total ghrelin concentrations. Nine men and nine women participated in the study. Their mean physical characteristics were as follows: age 24.8 (s(x) = 0.9) years, body mass index 22.9 (s(x) = 0.6) kg x m(-2), maximal oxygen uptake (VO(2max)) 57.7 (s(x) = 2.2) ml x kg(-1) x min(-1). The participants completed two 3-h trials (exercise and control) on separate days in a randomized balanced design after overnight fasts. The exercise trial involved a 1-h treadmill run at 73.5% of VO(2max) followed by 2 h of rest. The control trial consisted of 3 h of rest. Blood samples were collected at 0, 0.5, 1, 1.5, 2, and 3 h. Total ghrelin concentrations were determined from plasma. Hunger was assessed following blood sampling using a 15-point scale. The data were analysed using repeated-measures analysis of variance. Hunger scores were lower in the exercise trial than in the control trial (trial, P = 0.009; time, P < 0.001; trial x time, P < 0.001). Plasma total ghrelin concentrations did not differ between trials. These findings indicate that treadmill running suppresses hunger but this effect is not mediated by changes in plasma total ghrelin concentration.  相似文献   
6.
Abstract

In this study, we compared the effects of accumulated and continuous running on resting arterial blood pressure. Ten normotensive/pre-hypertensive men, aged 25.0 ± 4.2 years (mean ± s), participated in three 2-day trials at least one week apart in a randomized, repeated-measures design. On Day 1, participants rested (control) or ran at 70% of maximum oxygen uptake in either ten 3-min bouts (30 min rest between bouts) or one continuous 30-min bout. On Day 2, participants rested throughout the day. Blood pressure was measured at hourly intervals throughout Days 1 and 2. Mean resting systolic blood pressure on Day 2 was 6% lower during the accumulated and continuous running trials compared with the control trial (110 ± 6 vs. 110 ± 8 vs. 117 ± 6 mmHg respectively; P < 0.05), but there were no differences in resting diastolic blood pressure among the three trials (70 ± 7 vs. 69 ± 6 vs. 70 ± 5 mmHg respectively). These findings demonstrate that accumulating 30 min of running throughout the day in short bouts is as effective as 30 min of continuous running for reducing resting systolic blood pressure on the next day in young normotensive/pre-hyptertensive men.  相似文献   
7.
The within-trial contrast hypothesis (WTC) provides a more parsimonious explanation for the phenomenon that humans and animals prefer outcomes that follow more effortful events to outcomes that follow less effortful events (Zentall, 2013). We conducted two WTC experiments with human adults. In Experiment 1, we manipulated the difficulty of a preceding event by varying the interresponse time and the limited-hold interval during differential reinforcement with a low response rate schedule, to examine the effect of effort on the preference for the subsequent stimuli. In Experiment 2, we attempted to identify the variables that had affected the results of Experiment 1, by manipulating time as the delay of reinforcement. The results showed preferences based on WTC only when participants made a high rate of incorrect responses in the preceding event, which was used as an index of the strength of individual effort. These results extend the findings of previous human WTC studies and suggest that the difficulty of a task could serve as an aversive event that affects the WTC effect. It is possible that an index based on performance in the preceding event would provide useful information for predicting the contrast effect.  相似文献   
8.
In this study, we compared the effects of accumulated and continuous running on resting arterial blood pressure. Ten normotensive/pre-hypertensive men, aged 25.0 ± 4.2 years (mean ± s), participated in three 2-day trials at least one week apart in a randomized, repeated-measures design. On Day 1, participants rested (control) or ran at 70% of maximum oxygen uptake in either ten 3-min bouts (30 min rest between bouts) or one continuous 30-min bout. On Day 2, participants rested throughout the day. Blood pressure was measured at hourly intervals throughout Days 1 and 2. Mean resting systolic blood pressure on Day 2 was 6% lower during the accumulated and continuous running trials compared with the control trial (110 ± 6 vs. 110 ± 8 vs. 117 ± 6 mmHg respectively; P < 0.05), but there were no differences in resting diastolic blood pressure among the three trials (70 ± 7 vs. 69 ± 6 vs. 70 ± 5 mmHg respectively). These findings demonstrate that accumulating 30 min of running throughout the day in short bouts is as effective as 30 min of continuous running for reducing resting systolic blood pressure on the next day in young normotensive/pre-hyptertensive men.  相似文献   
9.
Abstract

This study examined associations between four health-related physical fitness measures and obesity in Taiwanese youth aged 10–18 years. Data from 13,500 school-aged youth were randomly selected from the “School Physical Fitness Database” of Taiwan by sex and age. Variables examined were height, body mass and performance on modified sit-and-reach (flexibility), bent-leg sit-up (abdominal muscular strength/endurance), standing long jump (lower body explosive strength) and distance run/walk (cardiorespiratory endurance). Adjusted logistic regression analyses were performed. Increased odds of being obese with decreased fitness levels were observed for lower body explosive strength and cardiorespiratory endurance in both sexes. The highest odds of being obese was found in the least fit quintile of cardiorespiratory endurance compared with the most fit quintile both in boys (Odds ratio, OR = 10.44; 95% confidence interval (CI), 7.94–13.73) and girls (OR = 5.40; 95% CI, 3.90–7.47). These findings suggest that in addition to cardiorespiratory fitness, lower body explosive strength is also associated with childhood and adolescent obesity.  相似文献   
10.
Abstract

Head impacts resulting in a concussion negatively affect the vestibular system, but little is known about the effect of subconcussive impacts on this system. This study’s objective was to determine if subconcussive head impacts sustained over one competitive lacrosse season, effect sway velocity. Healthy Division I male lacrosse players (n = 33; aged 19.52 ± 1.20 years) wore instrumented helmets to track head impact exposures. At the beginning and end of the season the players completed an instrumented Balance Error Scoring System assessment to assess sway velocity. Score differentials were correlated to the head impact exposure data collected via instrumented helmets when averaged within participant. Paired samples t-tests revealed a post-season increase in sway velocity on the double leg stance, firm surface (p = 0.002, d = 0.59); tandem stance, firm surface (p = 0.033, d = 0.39) and double leg, foam surface (p = 0.014, d = 0.45) A significant correlation was found between change in tandem stance, firm surface sway velocities and linear acceleration (p < 0.001, r = 0.65). It appears subconcussive impacts may result in tandem stance balance deficits. Repetitive head impacts may negatively affect sway velocity, even in the absence of a diagnosed concussion injury.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号