1,720,968 research outputs found
The effects of low energy availability (LEA) on metabolism, bone, reproductive markers, and mood states in endurance runners
No full textLow energy availability (LEA) occurs when there is insufficient dietary energy intake to account for energy needed for exercise and to sustain daily physiological functions. LEA tends to manifest more in physically active populations (i.e., athletes), and when unaddressed can lead to undesirable health and performance outcomes. Literature suggests that individual involved in endurance running are prone to LEA due to the high training demands that are not matched by concomitant high energy intake. However, the reported prevalence of LEA in endurance runners is widespread, ranging from 6%-92%, partly because of the variety of methods that can identify LEA. Furthermore, these methods are mostly validated in females, even though existing studies have used them in both sexes. The common methods are the Low Energy Availability in Females Questionnaire (LEAF-Q), measured Energy Availability (EA) of ≤ 30 kcal/kg Fat Free Mass (FFM)/ day, and a Resting Metabolic Rate (RMR) ratio ≤ 0.90. Therefore, the main aims of the thesis were: (i) to examine the prevalence of LEA risk and its association(s) with related risk factors in endurance runners in Singapore (Study 1); (ii) compare the methods of LEA risk identification (LEAF-Q, measured EA, RMRratio) and determine which have stronger association(s) with LEA risk factors and markers (Study 2); and (iii) investigate the short-term effects of LEA on associated risk markers (metabolism, bone, reproductive, and psychological) in male endurance runners (Study 3). Findings from this thesis can potentially inform practitioners and/or researchers of how to better detect LEA early. They could also improve guidance for athletes on how to better attain optimal EA via dietary energy intake to account for their exercise energy expenditure and daily physiological functions.Study 1 included 126 endurance runners (47 females, 79 males) who completed an online questionnaire that included self-reported items related to participants’ characteristics: height and weight, exercise/ training frequency and intensity, and questionnaires on disordered eating, exercise addiction, LEA, and the Male Athlete Triad. Study 2 was conducted as a cross-sectional study design which involved 20 male and 20 female endurance runners from Study 1. The participants completed several measurements in the laboratory – RMR, blood markers (metabolism, bone turnover, and reproductive), and a maximal oxygen uptake test (V̇ O2max) test. The participants were classified as at-risk of LEA and not-at-risk of LEA based on the LEAF-Q, self-reported three-day food diary and exercise log (measured EA), and RMRratio. Study 3 was an experimental study that used a randomised, repeated measures study design with three conditions of controlled EA (15, 30, 45 kcal/kgFFM/day) on 12 male endurance runners. Each EA condition lasted for a period of four days, through a controlled DEI (prescribed meal plans) and EEE (standardised exercise protocol).The findings from this thesis showed that a substantial proportion (18-50%) of endurance runners at LEA risk, with more males at risk than females. The prominent risk factors associated with LEA risk were disordered eating (measured by SCOFF questionnaire, and Brief Eating Disorder in Athletes Questionnaire), and exercise addiction (Exercise Addiction Inventory), suggesting that LEA can possibly be managed by targeting these factors. Secondly, the existing methods to identify LEA risk do not clearly differentiate between at risk and not at risk, as there were few significant differences in biomarkers between the two groups. Therefore, future studies need to refine and (re)validate the cut-offs in both sexes to improve the sensitivity of LEA identification. Lastly, short term LEA at 15kcal/kgFFM/day decreased testosterone and increased fatigue in male runners. These signs have the potential to be used as early markers of LEA in male runners. Endurance runners and individuals who play a role in athletes’ health and performance, including coaches, clinicians, etc, can apply this thesis’ findings to better understand how LEA can be identified, prevented, and managed, by measuring markers such as testosterone and mood states, and monitoring risk factors such as disordered eating on a regular (annual) basis.</p
Prevalence of relative energy deficiency in sport (red-s) risk amongst amateur and recreational athletes in Singapore
No full textBackground: Relative Energy Deficiency in Sport (RED-S) is a syndrome caused by low energy availability (LEA), that impairs physiological and psychological functions. There are no reports on the prevalence of RED-S risk amongst athletes in Singapore. This evidence can
identify those at risk, and institute measures for primary prevention of energy deficiency. Purpose of study: This study investigated the prevalence of RED-S risk, within athlete types (amateur, recreational), and between genders. Methods: 318 participants (124 males; 194 females) from Singapore, completed an online questionnaire which included – self-reported height and weight, Eating Disorder
Examination Questionnaire (EDE-Q) and Hooper’s Questionnaire, to determine RED-S risk. Results: The prevalence of RED-S risk amongst athletes was 34.3%. The prevalence of REDS risk in female athletes (44.3%) was significantly higher than males (18.5%), while the prevalence of RED-S risk amongst amateur and recreational athletes was not significantly different. RED-S risk was negatively associated with level of competition (international) and BMI, and positively associated with shape and weight concern scores. Conclusion: The moderate-high prevalence of RED-S risk emphasises the need for prevention
and early detection of energy deficiency, to preserve health and sport performanc
Prevalence of relative energy deficiency in sport (red-s) risk amongst amateur and recreational athletes in Singapore
No full textBackground: Relative Energy Deficiency in Sport (RED-S) is a syndrome caused by low energy availability (LEA), that impairs physiological and psychological functions. There are no reports on the prevalence of RED-S risk amongst athletes in Singapore. This evidence can
identify those at risk, and institute measures for primary prevention of energy deficiency. Purpose of study: This study investigated the prevalence of RED-S risk, within athlete types (amateur, recreational), and between genders. Methods: 318 participants (124 males; 194 females) from Singapore, completed an online questionnaire which included – self-reported height and weight, Eating Disorder
Examination Questionnaire (EDE-Q) and Hooper’s Questionnaire, to determine RED-S risk. Results: The prevalence of RED-S risk amongst athletes was 34.3%. The prevalence of REDS risk in female athletes (44.3%) was significantly higher than males (18.5%), while the prevalence of RED-S risk amongst amateur and recreational athletes was not significantly different. RED-S risk was negatively associated with level of competition (international) and BMI, and positively associated with shape and weight concern scores. Conclusion: The moderate-high prevalence of RED-S risk emphasises the need for prevention
and early detection of energy deficiency, to preserve health and sport performanceBachelor of Science (Sport Science and Management
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
