1,721,012 research outputs found
Heart Rate and GPS data analysis of Kiteboard course racing during the Italian Championship
No full textBackground. Despite the growing popularity of kiteboard course racing, there is a paucity of scientific literature about the performance in this sport.
Purpose. The aim of the present study was to analyze displacement (speed and direction) and heart rate (HR) data in high-level kiteboarders during competition.
Methods. Five kiteboarders, ages 33.8 ± 5.3 years, weight: 80.6 ± 4.8 kg, height: 181.2 ± 7.8 cm, were monitored with a GPS receiver and a HR monitor during four races of the Italian Kiteboarding Championship for a total of 46 regattas.
Results. Each regatta lasted 926 ± 175 s and was composed by 11 ± 1 beats. The average sailing speed recorded in competition was 8.9 ± 0.9 m/s. The speed was higher (p < 0.01) in the downwind leg (9.9 ± 1.4 m/s) than in the upwind leg (7.9 ± 0.3 m/s). The orientation of the kiteboard with respect to the wind direction during the upwind sailing phase was 66.4° ± 6.3°, resulting in been wider than in traditional sailing sports. The mean HR was 82.7 ± 0.9 % of HRreserve and 86% ± 1.2 HRmax, showing a relatively high exercise intensity compared to most of other sailing sports.
Conclusion. The duration and intensity of a kiteboard racing suggest the need of specific physical training programs for competitive kiteboarders
Sex differences in perceived physical activity characteristics in 11-19 years old italian students
No full textPurpose. This study aimed to investigate sex and age differences in selected physical characteristics assessed with questionnaires in a cohort of middle and high school students.
Methods. 1051 students (497 girls and 654 boys) aged 11 to 19 years completed the following questionnaires: Physical Activity Questionnaire for Adolescents (PAQ-A), Task and Ego Orientation in Physical Education Questionnaire (TEOSQ), Physical Activity Enjoyment Scale Questionnaire (PACES), Teacher-Initiated Motivational Climate in Physical Education Questionnaire (TIMCPEQ), Physical Self Description Questionnaire (PSDQ), and Psychobiosocial states questionnaire (PBS). For all questionnaires, scores were compared by sex and age with two-way ANOVAs.
Results. Overall, boys showed higher scores than girls in the PAQ-A, TEOSQ (ego orientation), TIMCPEQ, PBS (both pleasant and unpleasant descriptors), PACES (positive items), and PSDQ. Conversely, girls showed higher scores than boys in the PACES (negative items).
A trend of questionnaires scores to decrease across ages was observed, both in boys and girls, in the PAQ-A, PBS (pleasant descriptors), and PACES (positive items). Furthermore, decreases across ages of TEOSQ (task orientation) and PACES (negative items) were observed only in boys, while the PSDQ score decreased only in girls. Finally, boys showed an increase across age of the TEOSQ (ego orientation) score.
Conclusions. The present study confirms a decrease of motivation towards PA and PA enjoyment across adolescence and in particular in the transition between the middle and high school (at age 14). The study findings provide suggestions to PE teachers about the importance of using motivational strategies towards students, differentiated by sex and age groups
Fenomeni evolutivi delle pratiche motorie e sportive in ambiente esterno
No full textGli anni recenti hanno visto un’evoluzione nella pratica degli sport outdoor. Infatti sia in ambito ricreativo che competitivo sono emerse nuove discipline e tipologie di manifestazioni. In questo capitolo, partendo col definire cosa si intende con sport outdoor, verranno analizzati gli sport tradizionali, propriamente detti (istituzionalizzati) e genericamente intesi (come pratica saltuaria). Successivamente verranno prese in esame le pratiche motorie e sportive outdoor sviluppatesi più di recente, come i playground, i lifestyle sport e gli adventure sport. Accomunati dall’intento di distaccarsi dagli sport tradizionali, questi ultimi vengono presentati attraverso l’analisi dei numerosi elementi comuni che li caratterizzano, ed attraverso i quali hanno raggiunto una sempre maggiore popolarità. Verrà inoltre considerato come, partendo dalla semplice camminata di alcune ore fino ad arrivare alle gare epiche, l’interesse per queste attività è oggetto di studio e promozione nei più svariati settori, a cominciare dagli studi sociologici e psicologici per passare a quelli di industrie che realizzano materiali tecnici, fino alle campagne pubblicitarie finalizzate alla promozione di aree turistiche
Anthropometry, Physical and Movement Features, and Repeated-sprint Ability in Soccer Players
No full textThis study aimed to evaluate the associations of anthropometry, functional movement patterns (FMP) and physical performance characteristics with repeated-sprint ability (RSA) in male youth soccer players. Thirty six athletes (ages 16.6±0.5 years, BMI 22.0±1.3 kg/m2) completed the RSA test and other physical tests including countermovement jump with (CMJA) and without the help of arms (CMJ), 10-m and 20-m straight-line sprints, Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo), and functional movement screen (FMS). In addition, a battery of anthropometric variables was measured. RSA performance components such as best time (BT), mean time (MT) and sprint decrement were calculated. Results showed that measures of physical performance derived from horizontal plane in 10-m and 20-m sprints, were more strongly associated (p<0.01) with RSA performance than those obtained with CMJ or CMJA (p<0.05). High correlations (p<0.01) were found between MT, BT and Yo-Yo distance (r=-0.79, r=-0.67, respectively), as well as with FMS scores (r=-0.68, r=-0.58, respectively). Anthropometric measures, such as fat mass, upper fat area, thigh fat area, calf muscle area, and endomorphy were associated with RSA components (p<0.05). Predictors for the RSA performance identified in the stepwise multivariate analysis included Yo-Yo distance, time in sprints, FMP, and calf muscle area
A three-dimensional analysis of shot putting in elite male Italian athletes.
No full textPurpose: The aim of this study was to analyze the shot put biomechanics in the best male Italian shot put throwers (ISP) and to
compare their technical characteristics with those of world class athletes (WC) described in previous investigations.
Methods: The best six Italian shot putters of the year 2016 (age 20.2 ± 3.6 yrs, PB 18.44 ± 1.26 m) were recorded using three video
cameras FULL HD (60 frames/s, 1920x1080 pixel) while competing at the Italian Athletics Championships. For each athlete, the best
attempt was considered for 3D analysis, performed using SIMI Motion (Simi Reality Motion Systems GmbH, Unterschleissheim,
Germany). A selection of relevant technical parameters wasexamined.
Results: We observed some meaningful differences between ISP and WC. In particular, ISP showed shorter shot trajectories during the
double support phase (DSP) compared to WC (1.29 ± 0.23 cm vs 1.61 ± 0.14 cm, respectively) and overall a lower release velocity (12.25 ± 1.04 m/s vs. 13.73 ± 0.26 m/s, respectively). In addition, at the start of DSP, WC showed a more flexed right knee than ISP (120
to 140 vs 94 to 117, respectively) and the throwing arm parallel to the ground, unlike ISP that showed an angle of 33 ± 18 between the arm and the ground.
Conclusions: The analysis underlined some technical errors of ISP compared to WC throwers. The inferior performance of ISP compared to WC may be related to a lower release velocity, that previous research1,2 identified as the most important parameter for performance. The reduction of release velocity could be linked to shorter shot trajectories during DSP. At the start of DSP, ISP showed a
different right arm and knee position as compared to WC, and probably this difference explained the shorter trajectory, the lower
release velocity of the shot and, therefore, the lower level performance of ISP. Coaches should be aware that body position at DSP has
to be improved in order to extend the shot trajectory and improve release velocity.
References
1. Gutierrez-Davila M et al. (2009) Biomechanical analysis of the shot put at the 12th IAAF World Indoor Championship. New Studies in Athletics 24: 3-45
2. Goss-Sampson MA, Chapman M (2003) Temporal and kinematic analysis of the rotational shot put technique. Journal of Sports
Sciences 21: 237-23
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
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