Effects of caffeine on time trial performance in sedentary men     

George Laurence  Karen Wallman  Kym Guelfi 《Journal of sports sciences》2013,31(12):1235-1240

Abstract

It is not known if ergogenic effects of caffeine ingestion in athletic groups occur in the sedentary. To investigate this, we used a counterbalanced, double-blind, crossover design to examine the effects of caffeine ingestion (6 mg · kg^?1 body-mass) on exercise performance, substrate utilisation and perceived exertion during 30 minutes of self-paced stationary cycling in sedentary men. Participants performed two trials, one week apart, after ingestion of either caffeine or placebo one hour before exercise. Participants were instructed to cycle as quickly as they could during each trial. External work (J · kg^?1) after caffeine ingestion was greater than after placebo (P = 0.001, effect size [ES] = 0.3). Further, heart rate, oxygen uptake and energy expenditure during exercise were greater after caffeine ingestion (P = 0.031, ES = 0.4; P = 0.009, ES = 0.3 and P = 0.018, ES = 0.3; respectively), whereas ratings of perceived exertion and respiratory exchange ratio values did not differ between trials (P = 0.877, ES = 0.1; P = 0.760, ES = 0.1; respectively). The ability to do more exercise after caffeine ingestion, without an accompanying increase in effort sensation, could motivate sedentary men to participate in exercise more often and so reduce adverse effects of inactivity on health.  相似文献   

Space Science: the View from European School Students     

DeWitt  Jennifer  Bultitude  Karen 《Research in Science Education》2020,50(5):1943-1959

Research in Science Education - Gender imbalance in the physical sciences and engineering is a longstanding and well-documented concern within science education, industry, and policy. The current...  相似文献   

Journalists’ Perceptions of Mass Shooting Coverage and Factors Influencing Those Perceptions*     

Nicole Smith Dahmen  Jesse Abdenour  Karen McIntyre 《Journalism Practice》2019,13(8):895-900

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Re-conceptualizing embodied pedagogies in physical education by creating pre-text vignettes to trigger pleasure ‘in’ movement     

Karen Lambert 《Physical Education & Sport Pedagogy》2020,25(2):154-173

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Where Infants Go: Real-Time Dynamics of Locomotor Exploration in Crawling and Walking Infants     

Justine E. Hoch  Jaya Rachwani  Karen E. Adolph 《Child development》2020,91(3):1001-1020

Where do infants go? A longstanding assumption is that infants primarily crawl or walk to reach destinations viewed while stationary. However, many bouts of spontaneous locomotion do not end at new people, places, or things. Study 1 showed that half of 10- and 13-month-old crawlers’ (N = 29) bouts end at destinations—more than previously found with walkers. Study 2 confirmed that, although infants do not commonly go to destinations, 12-month-old crawlers go to proportionally more destinations than age-matched walkers (N = 16). Head-mounted eye tracking revealed that crawlers and walkers mostly take steps in place while fixating something within reach. When infants do go to a destination, they take straight, short paths to a target fixated while stationary.  相似文献   

Sports and Identity: New Agendas in Communication     

Karen L. Hartman 《Quarterly Journal of Speech》2016,102(2):208-211

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The role of gratitude in enhancing the relationship between doctoral research students and their supervisors     

Kerry Howells  Karen Stafford  Rosanne Guijt  Michael Breadmore 《Teaching in Higher Education》2017,22(6):621-638

While increasing attention is being placed on the crucial importance of a positive supervisor–student relationship, few studies have investigated how to enhance this. Our paper investigates the effect of gratitude practices, proposing it brings both focus and intentionality to the student–supervisor relationship resulting in better research outcomes and, by implication, a positive impact on attrition rates. Recent research has demonstrated that increased attention to gratitude can enhance relational well-being, but only a few studies investigate the role of gratitude in the higher education context. This qualitative case study explores the impact of gratitude as an intervention, following eight Ph.D. students and their two supervisors, in the schools of physical sciences, and medicine over a six-week period of focused attention on practices of gratitude. Findings revealed that all participants noted a positive impact in the areas of communication, social and emotional well-being, as well as on the research process itself.  相似文献   

Disaster planning in a health sciences library: a grant-funded approach     

Felicia Yeh  Karen D McMullen  Laura T Kane 《Journal of the Medical Library Association》2010,98(3):259-261

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Social effects on spatial choice in the radial arm maze     

Michael F. Brown  Toni-Moi N. Prince  Karen E. Doyle 《Learning & behavior》2009,37(3):269-280

Social memory was investigated in the context of a spatial working memory task. Pairs of rats were tested in an eight-arm radial maze. Under most conditions, there was a tendency to choose maze locations that had been visited earlier by the other rat. The possibility that this tendency is produced by common preferences for particular maze locations was ruled out. An opposite tendency to avoid visits to locations that had been visited earlier during the trial by another rat was found only when the maze location contained two pellets (rather than an undepletable supply), the rats’ ability to see each other in the maze was restricted to the central arena, and the maze location had been previously visited by the focal rat. The amount of food available in maze locations did not otherwise modulate social influences on spatial choice. The results indicate that memory for a rat’s own previous choices is combined with memory for the choices made by another rat.  相似文献   

Early Childhood Teachers' Ideas about Including Children with Disabilities in Programmes Designed for Typically Developing Children     

Hsin‐Hui Huang  Karen E. Diamond 《International Journal of Disability, Development & Education》2009,56(2):169-182

This study examined the influence of information about children's disabilities on preschool teachers' responses toward integrating children with disabilities in their classroom. Of particular interest was whether the severity of the child's educational needs and information about diagnosis were related to teachers' responses. Data were collected from 155 preschool teachers in two Midwest states in the United States to examine their responses in terms of levels of comfort, classroom adaptation, and need for support. Results showed that teachers responded differently to the types of disability regardless of the diagnostic labels; that is, teachers responded more positively to children with mild disabilities (e.g., children with Down syndrome) and those with physical disabilities (e.g., cerebral palsy). In addition, compared with children with diagnostic labels, teachers responded more positively to those with no diagnostic labels. Teachers' education and experience working with children with disabilities were associated with their levels of comfort. Implications and recommendations for service delivery and teacher training are discussed.  相似文献