1,721,006 research outputs found
Sex differences in aerobic fitness in top-class soccer referees
No full textCastagna, C, Bizzini, M, D'Ottavio, S, and Araújo Póvoas, SC. Sex differences in aerobic fitness in top-class soccer referees. J Strength Cond Res 32(11): 3216-3221, 2018-The aim of this study was to assess the aerobic-fitness differences between male and female top-class soccer field referees (FRs). This with the purpose to provide cutoff values useful for training prescription in female FRs. Forty female top-class FRs (age 34.18 ± 3.50 years and 5 ± 3.9 years international refereeing experience) and 52 male FRs (age 38.4 ± 3.3 years and 5 ± 3.5 years international refereeing experience) candidates in the preliminary open list developed by the FIFA Refereeing Department for the 2014 and 2015 World Cup Tournaments, participated in the study. The FRs were tested for aerobic fitness under laboratory conditions with a progressive speed treadmill test until exhaustion. Female FRs showed to possess, on average, lower (large effect) levels of aerobic fitness and performance compared with their male counterparts. The female FRs' V[Combining Dot Above]O2max (48.1 ± 4.4 ml·kg·min) was 7% (large effect) lower than the male FRs (51.9 ml·kg·min). Peak treadmill speed was 11% lower (large effect) in female FRs (16.27 ± 0.94 vs. 14.64 ± 0.96 km·h). The receiver operating characteristic curve analysis enabled cutoff values (47.8 ml·kg·min for V[Combining Dot Above]O2max) that may be used as preliminary cues to guide physiological selection and training prescription in female FRs aiming to officiate male-soccer matches. Only 2.5% of the female FRs showed V[Combining Dot Above]O2max higher than the mean values of male FRs when using the scaled notation (0.68). Female FRs aiming to officiate male competitions should consider training intensities at anaerobic threshold speed (13 km·h, 95% heart rate max) when developing aerobic fitness. Given the very large sex differences in aerobic performance, strength/power training should be proposed to perspective female top-class FRs
Aerobic Fitness in Top-Class Soccer Referees
No full textCastagna, C, Bizzini, M, Araújo Póvoas, SC, Schenk, K, Büsser, G, and D'Ottavio, S. Aerobic fitness in top-class soccer referees. J Strength Cond Res 33(11): 3098-3104, 2019-The aim of this study was to examine the aerobic fitness status of top-class male soccer officials using a cross-sectional design and known population group constructs. Fifty-two field referees (FRs, age 38.4 ± 3.3 years; height 181 ± 5.6 cm; body mass 76.8 ± 6.8 kg; body mass index [BMI] 23.4 ± 1.7 kg·m; body fat 20.4 ± 3.6%; and international refereeing experience 5 ± 3.5 years) and 104 assistant referees (ARs, age 37.8 ± 4.1 years; height 176.9 ± 7.5 cm; body mass 72.1 ± 7.4 kg; BMI 23 ± 1.6 kg·m; body fat 19.2 ± 3.6%; and international refereeing experience 7 ± 3.8 years) from 53 National Football Associations worldwide, and candidates of the preliminary open-list developed by the FIFA Refereeing Department for the 2014 World Cup Final Tournament, were tested for aerobic fitness in laboratory conditions with a progressive speed treadmill test to exhaustion. Large (+8.54%, d = 0.8) and small (+3.1%, d = 0.3) differences in absolute (L·min) and relative (ml·kg·min) VO2max were found between FR and AR, respectively. Trivial differences (d = 0.07) were shown in running economy (RE) (6 minutes at 8 km·h) between AR and FR. Using the scaling notation (b = 0.64), medium and significant differences were found between match officials for VO2max and RE (FR > AR; d = 0.6 and 0.67, respectively). Using receiver operating characteristic curve statistics, cutoff values of 3.93 L·min and 50.6 ml·kg·min were detected in absolute and relative VO2max for the FR and the AR (FR > AR), respectively. The FR showed superior aerobic fitness compared with AR. Training prescription should consider intensities at anaerobic threshold speed (14 km·h, 91% heart rate max) when aerobic fitness development is the aim in elite officials
Timing Effect on Training Session Rating of Perceived Exertion in Top-Class Soccer Referees
No full textTo examine the effect of recall timing on training session rating of perceived exertion (S-RPE) in a population of method procedures well-familiarized athletes, during a 5-days training micro-cycle
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
Physiological and performance responses to the FIFA 11+ (part 2): a randomised controlled trial on the training effects.
No full textThe aim of this study was to examine the training effects of an injury prevention programme on neuromuscular control, strength and performance in male amateur football players.
Eighty-one players were allocated to the “FIFA 11+” (n = 42) or a control group (CON, n = 39). The “FIFA 11+” group performed the programme 3 times a week for 9 weeks; the control group completed the usual warm-up. Primary outcomes were: time-to-stabilisation test and eccentric/concentric flexors strength. Secondary outcomes were: eccentric/concentric extensors strength, star excursion balance test, core-stability test, vertical jump, sprint, and agility.
After controlling for covariates, significant between-group differences after the intervention (in favour of the “FIFA 11+” players) were found for time-to-stabilisation (-2.8%, 90% confidence interval [CI] -4.4 to -1.2%) and core-stability (-8.9%, -14.6 to -3.1%). Differences were also found for eccentric (3.8%, 1.4 to 6.2%) and concentric flexors strength (3.2%, 0.6 to 5.9%) at 60° · s−1 but this difference was only possibly meaningful (62.4%) from a practical point of view. No substantial and/or significant differences were found for the other outcomes.
Performing “FIFA 11+” for 9 weeks can improve neuromuscular control. Possible worthwhile differences were found for flexors strength but there were no substantial effects in the other performance measures
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
- …
