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61.
Paolo Bardella Irene Carrasquilla García Marco Pozzo Julio Tous-Fajardo Eduardo Saez de Villareal 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(1):102-114
The purpose of this study was to analyse the raw lifting speed collected during four different resistance training exercises to assess the optimal sampling frequency. Eight physically active participants performed sets of Squat Jumps, Countermovement Jumps, Squats and Bench Presses at a maximal lifting speed. A linear encoder was used to measure the instantaneous speed at a 200 Hz sampling rate. Subsequently, the power spectrum of the signal was computed by evaluating its Discrete Fourier Transform. The sampling frequency needed to reconstruct the signals with an error of less than 0.1% was f99.9 = 11.615 ± 2.680 Hz for the exercise exhibiting the largest bandwidth, with the absolute highest individual value being 17.467 Hz. There was no difference between sets in any of the exercises. Using the closest integer sampling frequency value (25 Hz) yielded a reconstruction of the signal up to 99.975 ± 0.025% of its total in the worst case. In conclusion, a sampling rate of 25 Hz or above is more than adequate to record raw speed data and compute power during resistance training exercises, even under the most extreme circumstances during explosive exercises. Higher sampling frequencies provide no increase in the recording precision and may instead have adverse effects on the overall data quality. 相似文献
62.
Asier Mañas Borja del Pozo-Cruz Francisco José García-García Amelia Guadalupe-Grau 《European Journal of Sport Science》2017,17(7):940-953
Sedentary behaviour (SB) has recently emerged as an independent risk factor for different health outcomes. Older adults accumulate long time in SB. Understanding the role that SB plays on health is crucial for a successful aging. This short systematic review summarizes the current evidence related to the effects of objectively measured SB on frailty, physical performance and mortality in adults ≥60?years old. The literature search produced 271 records for physical performance (n?=?119), frailty (n?=?31), and mortality (n?=?121). Finally, only 13 articles fulfilled the inclusion criteria and were included in this review. All articles but one included in the physical performance section (n?=?9) showed a negative association between longer time spent in SB and physical performance. A significant association of SB with higher odds of frailty was found, however this association disappeared after adjusting for cognitive status. Lastly, two of the three included studies showed positive associations between SB and mortality, but this effect decreased or even disappeared in the more adjusted models. In conclusion, there is consistency that SB is negatively associated with physical performance. However, the relationship between objectively measured SB and frailty incidence and mortality rates remains unclear and deserves further research. The use of homogenous criteria to assess SB and the inclusion of more robust research designs will help clarifying the independent effects that SB could have on physical performance, frailty, and mortality. This will ultimately help designing more efficient and comprehensive physical activity guidelines for older adults. 相似文献
63.
Pedro Buendía 《Al-Masaq: Islam & the Medieval Mediterranean》2014,26(2):168-182
The history of ice in medieval Arab societies is obscured behind a mosaic of a variety of references and scholarly citations. Beyond al-Qalqashandī's reference to organised ice trafficking in fourteenth-century Mamluk Egypt, we do not have conclusive evidence on the origin and use of ice as a consumer product. In this paper we trace its presence based on three genres of references: historical and literary quotations, medicine and literature pertaining to food. These references allow us to consider the extent of ice consumption in the Arab world before the ninth century, as well as the existence of an organised trade throughout the Middle Ages from that time. However, contrary to the Persian world, with its well-documented Iranian yakhchals, we still know virtually nothing about ice-houses in medieval Arab societies. We also know very little about the profession of the thallāj or ice-seller, or whether the widespread consumption of ice that originated in Spain in the sixteenth century was in fact a legacy of an earlier trade in al-Andalus. 相似文献
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66.
Inmaculada M. García–Sánchez Marjorie Faulstich Orellana Megan Hopkins 《Multicultural Perspectives》2013,15(3):148-154
In this article Abraham Lincoln is considered as an alternative to the usual type of patriot's hero. He reminds us of our great historical failings. He remains a figure of controversy, a national hero in only some corners of society. He is the heroic President who serves as the first compassionate defender of the downtrodden, and he is a hero in those subcultures as well. Lincoln's treatment in the movies is discussed, focusing particularly on the recent movie Lincoln. Lincoln is seen as a match for the usual movie hero. His famous immunity to casual treatment in popular culture is discussed as well. 相似文献
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68.
Catherine B. Woods Kevin Volf Liam Kelly Blthín Casey Peter Gelius Sven Messing Sarah Forberger Jeroen Lakerveld Joanna Zukowska Enrique García Bengoechea PEN consortium 《运动与健康科学(英文)》2021,10(3):263-276
BackgroundDespite the well-established health benefits of physical activity (PA) for young people (aged 4–19 years), most do not meet PA guidelines. Policies that support PA in schools may be promising, but their impact on PA behavior is poorly understood. The aim of this systematic review was to ascertain the level and type of evidence reported in the international scientific literature for policies within the school setting that contribute directly or indirectly to increasing PA.MethodsThis systematic review is compliant with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Six databases were searched using key concepts of policy, school, evaluation, and PA. Following title and abstract screening of 2323 studies, 25 progressed to data synthesis. Methodological quality was assessed using standardized tools, and the strength of the evidence of policy impact was described based on pre-determined codes: positive, negative, inconclusive, or untested statistically.ResultsEvidence emerged for 9 policy areas that had a direct or indirect effect on PA within the school setting. These were whole school PA policy, physical education, sport/extracurricular PA, classroom-based PA, active breaks/recess, physical environment, shared use agreements, active school transport, and surveillance. The bulk of the evidence was significantly positive (54%), 27% was inconclusive, 9% was significantly negative, and 11% was untested (due to rounding, some numbers add to 99% or 101%). Frequency of evidence was highest in the primary setting (41%), 34% in the secondary setting, and 24% in primary/secondary combined school settings. By policy area, frequency of evidence was highest for sport/extracurricular PA (35%), 17% for physical education, and 12% for whole school PA policy, with evidence for shared use agreements between schools and local communities rarely reported (2%). Comparing relative strength of evidence, the evidence for shared use agreements, though sparse, was 100% positive, while 60% of the evidence for whole school PA policy, 59% of the evidence for sport/extracurricular PA, 57% of the evidence for physical education, 50% of the evidence for PA in classroom, and 50% of the evidence for active breaks/recess were positive.ConclusionThe current evidence base supports the effectiveness of PA policy actions within the school setting but cautions against a “one-size-fits-all” approach and emphasizes the need to examine policy implementation to maximize translation into practice. Greater clarity regarding terminology, measurement, and methods for evaluation of policy interventions is needed. 相似文献
69.
María Cristina Cardona Moltó 《欧洲特需教育杂志》2013,28(1):115-117
The current paper reports on the outcome of an ongoing action research project at a school for higher-functioning students with Autism Spectrum Disorder (ASD) in Sweden. The overall aim of the study was to develop and evaluate a questionnaire that captures social and individual aspects of classroom learning suitable for use with students with ASD. Interview data is presented on the perceived utility of the questionnaire for understanding and planning classroom instruction for the children with ASD through the eyes of the students’ teachers and their parents, as assessed during an Individual Education Plan meeting. Further, teacher ratings obtained by means of the instrument were found to differentiate a group of students with ASD (n = 10) from a group of typically developing children matched with regard to grade year, word reading ability and receptive vocabulary (n = 10). Implications and future directions are discussed, as are limitations of this pilot study. 相似文献
70.
Rodolfo herrero Ricaño Héctor Barrón Soto 《The American journal of distance education》2013,27(1):68-71
Abstract Since 1947, distance education in Mexico has had an important role for nonconventional populations. Considering that distance education is a heterogeneous and dynamic field, it is important to reflect on the need to improve quality as measured by our own standards. With that perspective in mind, a national meeting was organized to start a self‐diagnosis in which quality and access were the main concerns. Five hundred and twenty specialists from fifty‐one institutions participated in a national interactive synchronous meeting held in four regions. As a result of the meeting, thirty‐five criteria and 230 parameters of quality were established. The main conclusion of the meeting refers to the need for the elaboration of our own indicators for open and distance education. 相似文献