Rethinking fat as a fuel for endurance exercise

Abstract

A key element contributing to deteriorating exercise capacity during physically demanding sport appears to be reduced carbohydrate availability coupled with an inability to effectively utilize alternative lipid fuel sources. Paradoxically, cognitive and physical decline associated with glycogen depletion occurs in the presence of an over-abundance of fuel stored as body fat that the athlete is apparently unable to access effectively. Current fuelling tactics that emphasize high-carbohydrate intakes before and during exercise inhibit fat utilization. The most efficient approach to accelerate the body’s ability to oxidize fat is to lower dietary carbohydrate intake to a level that results in nutritional ketosis (i.e., circulating ketone levels >0.5 mmol/L) while increasing fat intake for a period of several weeks. The coordinated set of metabolic adaptations that ensures proper interorgan fuel supply in the face of low-carbohydrate availability is referred to as keto-adaptation. Beyond simply providing a stable source of fuel for the brain, the major circulating ketone body, beta-hydroxybutyrate, has recently been shown to act as a signalling molecule capable of altering gene expression, eliciting complementary effects of keto-adaptation that could extend human physical and mental performance beyond current expectation. In this paper, we review these new findings and propose that the shift to fatty acids and ketones as primary fuels when dietary carbohydrate is restricted could be of benefit for some athletes.     

Breaking the Cycle: Future Faculty Begin Teaching with Learner-Centered Strategies after Professional Development

The availability of reliable evidence for teaching practices after professional development is limited across science, technology, engineering, and mathematics disciplines, making the identification of professional development “best practices” and effective models for change difficult. We aimed to determine the extent to which postdoctoral fellows (i.e., future biology faculty) believed in and implemented evidence-based pedagogies after completion of a 2-yr professional development program, Faculty Institutes for Reforming Science Teaching (FIRST IV). Postdocs (PDs) attended a 2-yr training program during which they completed self-report assessments of their beliefs about teaching and gains in pedagogical knowledge and experience, and they provided copies of class assessments and video recordings of their teaching. The PDs reported greater use of learner-centered compared with teacher-centered strategies. These data were consistent with the results of expert reviews of teaching videos. The majority of PDs (86%) received video ratings that documented active engagement of students and implementation of learner-centered classrooms. Despite practice of higher-level cognition in class sessions, the items used by the PDs on their assessments of learning focused on lower-level cognitive skills. We attributed the high success of the FIRST IV program to our focus on inexperienced teachers, an iterative process of teaching practice and reflection, and development of and teaching a full course.     

A Methodology for Calculating Prestige Ranks of Academic Journals in Communication: A More Inclusive Alternative to Citation Metrics

The problem of how to rank academic journals in the communication field (human interaction, mass communication, speech, and rhetoric) is one of practical importance to scholars, university administrators, and librarians, yet there is no methodology that covers the field's journals comprehensively and objectively. This article reports a new ranking methodology based in empirical criteria. The new system relates independent measures of the prestige of the field's doctoral departments to information about where faculty members from those departments have published scholarly articles. This new approach identifies the field's most influential journals as those that more frequently publish the work of the field's top scholars and programs as perceived by their peers. This system was used to compute prestige weights (P-weights) for 65 communication journals. P-weights were found to be strongly correlated with ISI Web of Science journal impact factor scores and can be used to identify an overall prestige hierarchy for communication journals as well as prestige rankings by subject specialty.     

Job burnout and the school psychologist

School psychologists participating in a workshop on burnout completed Freudenberger's Burnout Questionnaire (1980), identified major job-related stressors, and responded to a list of suggested supervisory, individual, and organizational strategies for prevention. Slightly less than half of the participants appeared on the questionnaire to have burnout problems. Age, years of experience, and sex were not significantly related to the burnout score. Major identified stressors included excessive caseloads, lack of time, and lack of support or appreciation. Reactions to the strategies were positive and hopeful. Implications for training were drawn.     

Establishing the structure of reality for an industry: model and anti-model arguments as advocacy in Nike's crisis communication

This study illustrates the potential role of model and anti-model arguments in organizational crisis communication. Specifically, model and anti-model arguments are described as a strategy for moving the focus of a crisis from an organization to its industry. Model arguments enable organizations to establish their corrective action as industry standards that merit imitation. Conversely, organizations can set minimum standards for their industries with anti-model arguments. Phil Knight's May 12, 1998, speech announcing Nike's new initiatives in global manufacturing is analyzed as a case study. The essay concludes that model and anti-model arguments can suspend criticism of the organization, create the foundation for a return to industry prominence by the organization, and establish proposed new industry standards that are favorable to the organization.     

Teacher e-mail message strategies and students' willingness to communicate online

In light of the prevalent use of e-mail between teachers and students, researchers have highlighted the need to assess its uses and effects. Relying on the research and thinking of teacher immediacy and extra-class communication, we developed a scale that measures those e-mail message strategies that influence students' willingness to communicate online with their teachers. Next, we isolated those reasons that students use e-mail to interact with their teachers: (1) to clarify course material and procedures, (2) as a means of efficient communication, and (3) for personal/social reasons. Finally, we examined student characteristics such as gender and ethnicity, and history of e-mail use that may (or may not) influence their attitudes toward e-mail exchanges with teachers.     

Student & tutor consensus: a partnership in assessment for learning

The mistakes made when attempting tasks often prove to be some of the most invaluable learning experiences. Despite this, outcome and results driven assessment formats largely penalise student performance errors or reward students who succeed by chance. The consequences of this paradigm are visible effects on student relationships with assessment. The student–tutor consensus approach to assessment was introduced to capture student learning achieved ‘from’ assessment to complement the measurement of performance outcomes. This approach parallels student and tutor judgement in a grade negotiation, affording the student an opportunity to share with their assessor what they have learned from the assessment activity. This student self-awareness was then considered alongside the conventional outcome-based score awarded by the tutor to generate a final grade for the assessed activity. Our study evaluated the perceptions of 90 undergraduate students enrolled in the bachelor of paramedic studies, who participated in this novel assessment approach as part of a final-year capstone topic. The results comprehensively indicated value for all aspects of the assessment approach, as well as a recognition that the skills will be useful in their future professional roles.     

Is the Internet a US invention?—an economic and technological history of computer networking

Although the inventions embodied in the Internet originated in a diverse set of industrial economies, the US was consistently the source of critical innovations and an early adopter of new applications. Why did other nations, including several that made important inventive contributions to the Internet, not play a larger role in its development, particularly in the creation of new business organizations, governance institutions, and applications? We argue that the role of the US “national innovation system” in the creation of the Internet echoes several key themes of US technological development before 1940. The presence of a large domestic market, a set of antitrust and regulatory policies that weakened the power of incumbent telecommunications firms, and a diverse private/public research community that was willing to work with both domestic and foreign inventions were important preconditions for US leadership in computer networking innovation.