Sedentary behaviour and adiposity in elite athletes     

Pedro B. Júdice  João P. Magalhães  Catarina N. Matias  Luís B. Sardinha 《Journal of sports sciences》2013,31(19):1760-1767

Abstract

Overweight and obesity are defined as abnormal or excessive fat accumulation that presents a health risk. Even in athletes an increased adiposity affects health and performance. Sedentary behaviour has been associated with higher levels of adiposity, independent of moderate-to-vigorous physical activity. However, it is unclear whether this independent relationship still exists in highly trained athletes. The aim of this study was to examine the association of sedentary behaviour with body fatness in elite athletes. Cross-sectional data from 82 male athletes (mean age 22 years) were used. Total and regional body composition was measured by dual energy X-ray absorptiometry. Self-reported time spent in sedentary behaviour and weekly training time was assessed in all participants at one time point and multiple regression analyses were used. Sedentary behaviour predicted total fat mass (β = 0.77; 95% CI: 0.36–1.19, P < 0.001) and trunk fat mass (β = 0.25; 95% CI: 0.07–0.43, P = 0.007), independent of age, weekly training time, and residual mass (calculated as weight-dependent variable) but not abdominal fat. Also, no associations of sedentary behaviour with fat-free mass, appendicular lean soft tissue, and body mass index were found. These findings indicate that athletes with higher amounts of sedentary behaviour presented higher levels of total and trunk fatness, regardless of age, weekly training time, and residual mass. Therefore, even high moderate-to-vigorous physical activity levels do not mitigate the associations between sedentary behaviour and body fatness in highly trained athletes.  相似文献   

Effect of sulphurous mineral water in haematological and biochemical markers of muscle damage after an endurance exercise in well-trained athletes     

Marisol Soria  Santiago Esteva  Jesús F. Escanero  José R. Pina 《Journal of sports sciences》2013,31(10):954-962

Abstract

To investigate the effects of sulphurous mineral water (SMW) after a hydroponic treatment on muscle damage, antioxidant activity and peripheral blood changes induced by submaximal exercise. Thirty well-trained male triathletes were supplemented with SMW or placebo: 3 weeks of placebo, 30 days of wash out and 3 weeks of SMW. After both periods, participants ran for 2 h at 70% maximal aerobic speed. Antioxidant enzymes, lipid peroxidation, antioxidant capacity and blood cell markers were compared between placebo and SMW at pre-exercise (T₀), immediately post-exercise (T₁), 24 h post-exercise (T₂) and 48 h post-exercise (T₃). Total thiols decreased until T₃ vs. T₀ for both placebo and SMW; transient red blood cells, haemoglobin and haematocrit increased were shown at T₁ vs. T₀ and for leucocytes until T₂ vs. T₀, only for placebo group. Total thiols increased significantly in SMW vs. placebo at T₀; Thiobarbituric acid reactive species was significantly higher at T₀, T₁, T₂ and T₃; catalase increased significantly at T₁; creatine phosphokinase decreased significantly at T₁, T₂ and T₃, although no significant differences were found at T₀. Furthermore, red blood cells, haemoglobin and haematocrit were significantly higher and leucocytes were significantly lower at T₀ and T₁ in SMW group vs. placebo group. This study suggests that three weeks of SMW supplementation may protect from exercise-induced muscle damage.  相似文献   

The validity and reliability of a novel app for the measurement of change of direction performance     

Carlos Balsalobre-Fernández  Chris Bishop  José Vicente Beltrán-Garrido  Pau Cecilia-Gallego  Aleix Cuenca-Amigó  Daniel Romero-Rodríguez 《Journal of sports sciences》2013,31(21):2420-2424

ABSTRACT

The aim of the present investigation was to analyze the validity and reliability of a novel iPhone app (CODTimer) for the measurement of total time and interlimb asymmetry in the 5 + 5 change of direction test (COD). To do so, twenty physically active adolescent athletes (age = 13.85 ± 1.34 years) performed six repetitions in the COD test while being measured with a pair of timing gates and CODTimer. A total of 120 COD times measured both with the timing gates and the app were then compared for validity and reliability purposes. There was an almost perfect correlation between the timing gates and the CODTimer app for the measurement of total time (r = 0.964; 95% Confidence interval (CI) = 0.95–1.00; Standard error of the estimate = 0.03 s.; p < 0.001). Moreover, non-significant, trivial differences were observed between devices for the measurement of total time and interlimb asymmetry (Effect size < 0.2, p > 0.05). Similar levels of reliability were observed between the timing gates and the app for the measurement of the 6 different trials of each participant (Timing gates: Intraclass correlation coefficient (ICC) = 0.651–0.747, Coefficient of variation (CV) = 2.6–3.5%; CODTimer: ICC = 0.671–0.840, CV = 2.2–3.2%). The results of the present study show that change of direction performance can be measured in a valid, reliable way using a novel iPhone app.  相似文献   

Tannins characterization in historic leathers by complementary analytical techniques ATR-FTIR,UV-Vis and chemical tests     

Lina Falcão  Maria Eduarda M. Araújo 《Journal of Cultural Heritage》2013,14(6):499-508

This paper presents a complementary analytical approach to characterize vegetable tanning materials in historic leathers. It is described the application of two molecular spectroscopic techniques, ATR-FTIR and UV-Vis, and three specific chemical tests to analyse tannins present in leathers. Acid butanol, nitrous acid and rhodanine colorimetric tests, evaluated both visually and spectrophotometrically, were used to identify condensed tannins, ellagitannins and gallotannins, respectively. Ten samples of commercial, or laboratory prepared, vegetable tannins and seven new vegetable tanned leathers were also analysed and obtained results were used for comparison. The complete analytical procedure was performed, in a semi-micro-destructive scale, using fibres collected from leather. Analysis of ATR-FTIR and UV spectra of commercial and laboratory prepared vegetable tannins allowed the establishment of the characteristic bands of condensed and hydrolysable tannins and, more specifically, gallotannins. These data were used to confirm the type of vegetable tanning agents used in new leather extracts. The same approach was used in cultural heritage leathers, supported by the colorimetric tests, since protein degradation products were co-extracted in aged leathers and interfered in IR spectra.  相似文献   

The Prestige of Social Scientists in Spain and France: An Examination of Their h-Index Values Using Scopus and Google Scholar     

Dabós  Marcelo P.  Gantman  Ernesto R.  Fernández Rodríguez  Carlos J. 《Minerva》2019,57(1):47-66

We analyze the prestige of 1,500 scholars in economics, sociology, and management who have Spanish and French institutional affiliations operationalized by their h-index in Scopus and Google Scholar. We use a negative binomial count model to examine how some individual factors affect the h-index from both databases. The results show a non-monotonic relationship between the researchers’ career length and their h-index. There is a positive and statistically significant relationship between total research output and the h-index. The share of publications in English over total publications has also a positive and statistically significant effect on the h-index, except in a single case, while the share of publications in other foreign languages does not have such effect. Finally, we found that the effects of the number of citations received by documents in English (international impact) and by those in the vernacular language (local or regional impact) on the h-index vary according to the database, the country, and the discipline in question.

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Measurement in Physical Education and Exercise Science (MPEES): A Brief Report on 2019     

Nicholas D. Myers  André G. Bateman  Seungmin Lee  Stephen Silverman 《Measurement in physical education and exercise science》2020,24(2):93-102

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Predictors of student success in Higher Education: Secondary school internal scores versus national exams          下载免费PDF全文

José Miguel Cerdeira  Luis Catela Nunes  Ana Balcão Reis  Carmo Seabra 《Higher Education Quarterly》2018,72(4):304-313

In many countries entrance to Higher Education is determined by the performance of students in secondary school and/or the scores obtained in national exams. The relative weight of these two scores on the admission decision is a relevant policy topic, given its implication on who is admitted to university. The purpose of this paper is to investigate the relative predictive power of these two measures on the academic performance of students in Higher Education. It makes use of a dataset of Bachelor students from Portuguese Higher Education institutions with detailed information about their characteristics and past achievement results. The measure of academic achievement considered is the Bachelor's final average score. The main finding is that the scores given by teachers in secondary school are better predictors of subsequent performance than the access exam scores. The relevance of factors like working status, social support and gender vary with the reputation of the degree and the type of Higher Education institution, university versus polytechnic. A noteworthy result is that the added predictive contribution of parents' education is always negligible when past success measures are already taken into account.  相似文献   

Mature students’ access to higher education: A critical analysis of the impact of the 23+ policy in Portugal     

José Pedro Amorim 《European Journal of Education》2018,53(3):393-413

Increasing mature students’ access to higher education (HE) is a worldwide priority. In Portugal, the 23+ policy which was launched ten years ago opened HE to these students. A critical analysis of eight years’ data on the universe of mature candidates in HE in Portugal shows that this “opening” varies in inverse ratio to the social prestige of institutions and subject areas. The private polytechnics and the soft sciences display a greater receptiveness than the public universities and the hard sciences. This article demonstrates that mature students save the HEIs that are less sought-after by “traditional” students and argues for fairer access to the most prestigious HEIs and programmes.  相似文献   

Prediction of peak V˙O2 in Children and Adolescents With HIV From an Incremental Cycle Ergometer Test     

Luiz Rodrigo Augustemak de Lima  Diego Augusto Santos Silva  Paulo Cesar do Nascimento Salvador  Carlos Alencar Souza Alves Junior  Priscila Custódio Martins  João Antônio Chula de Castro 《Research quarterly for exercise and sport》2019,90(2):163-171

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The development of mental rotation abilities through robotics-based instruction: An experience mediated by gender     

José Antonio González-Calero  Ramón Cózar  Rafael Villena  José Miguel Merino 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(6):3198-3213

The research literature on the topic of “spatial ability” reveals that it has a major influence on achievement in the fields of science, technology, engineering and mathematics. Additionally, previous studies indicate the existence of a gender gap in spatial ability in favour of males. Mental rotation, one subskill of spatial ability, is an area in which gender differences are greater. At the same time, educational robotics is seen as one of the more promising technologies in educational contexts for the future. We conducted a quasi-experimental study with 142 seven- and eight-year-old students aimed at analysing whether robotics-based instruction may produce greater learning gains on mental rotation abilities compared to traditional instruction. The intervention was developed in the context of map-reading tasks, which are part of the curricular content in Mathematics and Social Sciences at this age. The results showed that for males, the robotics-based instruction promoted a significantly greater improvement in students’ mental rotation abilities compared to the control group. By contrast, no significant differences were observed for females. Although this study provides empirical evidence of the potential of robotics-based instruction, future studies need to deeply analyse the existence of gender differences in the learning gains obtained through educational robotics.  相似文献