1,720,976 research outputs found
Exercise prescription for health: Italian perspective. Italian guidelines for exercise prescription in healthy adults (18-65 years)
No full textExercise prescription has been widely deepened and discussed by National and International Organizations. Lack of physical activity has been demonstrated to be associated to premature all causes mortality and chronic diseases. Although developing an active lifestyle is one of the most effective preventive treatment for chronic diseases, more than 25% of adults doesn’t match the current guidelines about physical exercise around the world. The existing guidelines suggest the practice of moderate-intensity physical activity in combination with muscle-strengthening and flexibility exercises; none of them takes into consideration sedentariness and the amount of exercise performed during everyday-life activities. The aim of this article is to guide clinicians in exercise prescription by reviewing current international guidelines and introducing the new concept of “corrections factors”: the amount of sedentary time is converted in more minutes of physical exercise; daily-life activities (e.g. steps) lessen the amount of time a person should perform physical exercise. These guidelines are currently under review to be utilized by Italian Health system as fundamental reference for exercise prescription
Recommendations for altitude training programming to preserve athletes' health after the COVID-19 pandemic
No full textRecommendations for altitude training programming to preserve athletes' health after COVID-19 pandemic
No full textChanges in prefrontal cerebral oxygenation and microvascular blood volume in hypoxia and possible association with acute mountain sickness
Full text linkNew Findings: What is the central question of this study? The role of the cerebral haemodynamic response to either normobaric or hypobaric hypoxia in people susceptible to acute mountain sickness (AMS) is still under debate. Prefrontal cortex near-infrared spectroscopy-derived parameters were monitored in normobaric hypoxia at rest and during moderate-intensity exercise in AMS-prone and non-AMS individuals. What is the main finding and its importance? The AMS-prone individuals did not increase microvascular blood volume and showed lower prefrontal cerebral oxygenation in normobaric hypoxia both at rest and during exercise compared with non-AMS subjects, suggesting that these changes might underpin later development of AMS at altitude. Abstract: The aim of this study was to evaluate changes in prefrontal cerebral oxygenation and microvascular blood volume during exercise in normobaric hypoxia and to investigate possible associations with the occurrence of acute mountain sickness (AMS) at altitude. Twenty-two healthy individuals (age, 26 ± 4 years; peak oxygen uptake, 42 ± 4 ml kg−1 min−1) were tested in two different conditions: normoxia (NORM) and normobaric hypoxia (fraction of inspired O2 = 0.13; HYPO). Data were collected at rest and during submaximal constant-speed exercise. The peripheral oxyhaemoglobin saturation was measured by finger pulse oximeter. Changes in prefrontal cerebral oxygenation (ΔHbO2), deoxygenation (ΔHHb) and microvascular blood volume (ΔHbtot) were obtained by near-infrared spectroscopy. Within 2 weeks after laboratory testing, subjects rapidly ascended to 3647 m a.s.l., and AMS was evaluated using the Lake Louise scale. Eight subjects were AMS+, whereas 14 were AMS−. During NORM, near-infrared spectroscopy variables did not change from baseline values both at rest and during exercise, with similar results in AMS+ and AMS− subjects. During HYPO, ΔHHb increased to a similar extent in both groups, both at rest and during exercise. The ΔHbO 2 was significantly less in AMS+ compared with AMS− subjects, both at rest [−3.23 ± 5.90 versus 1.44 ± 2.14 μm, P = 0.04, effect size (ES) = 1.1, respectively] and during exercise (−6.56 ± 5.51 versus 0.37 ± 4.36 μm, P < 0.01, ES = 1.2, respectively). Total haemoglobin did not change from baseline, both at rest (−1.67 ± 9.53 μm) and during exercise (−0.96 ± 9.12 μm) in AMS+ subjects, which was significantly different from the AMS− group (5.49 ± 3.99 μm, P = 0.03, ES = 1.0 and 8.17 ± 7.34 μm, P = 0.02, ES = 1.0, respectively). Individuals prone to AMS seem to be unable to increase microvascular blood volume and to maintain oxygenation at the cerebral level during exercise in acute normobaric hypoxia, suggesting that these changes might underpin later development of AMS. </p
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
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