Effects of resistance training in HIV-infected patients: A meta-analysis of randomised controlled trials     

Roberto Poton  Marcos Polito  Paulo Farinatti 《Journal of sports sciences》2017,35(24):2380-2389

The relative effects of resistance training (RT) upon muscle fitness and immune function among HIV-infected patients are uncertain. The purpose of this study was to perform a meta-analysis to determine the effects of RT upon muscle strength, muscle mass and CD4 cells count and to identify potential moderators of those outcomes in HIV-infected patients. Meta-analyses use random or fixed-effects model depending on the heterogeneity of effect sizes, complemented with Hedge’s g correction factor. Thirteen trials were meta-analysed. Overall, RT increased muscle strength (35.5%, P < 0.01) and CD4 cell count (26.1%, P = 0.003) versus controls (P < 0.03), but not muscle mass (P = 0.051). Meta-regression followed by subgroup moderator analysis showed that gains in muscle strength followed a dose–response pattern with largest increase detected among trials with longer (24 weeks; 49.3%) than shorter intervention (<12 weeks; 39%), higher (Physiotherapy Evidence-Based Database [PEDro] scale = 6; 38.3%) than lower (PEDro = 5; 28.1%) quality, and longer (12 months; 59.7%) than shorter time under highly active antiretroviral therapy (HAART) (<6 months; 37.1%), (P < 0.01). RT appears to be efficacious to improve muscular strength (~35.5%) and CD4 cell count (~26.1%), but not muscle mass of HIV-infected patients. Effects upon strength were greater in studies with higher quality and among trials with longer RT and HAART.  相似文献   

Rice (Oryza sativa) Bran and Soybean (Glycine max) Meal: Unconventional Supplements in the Mead Production     

Geiza Suzart Araújo  Gislane Oliveira Ribeiro  Sílvia Maria Almeida de Souza  Gervsio Paulo da Silva  Giovani Brando Mafra de Carvalho  Jos Ailton Conceio Bispo  Ernesto Acosta Martínez 《Food Technology and Biotechnology》2022,60(1):89

  相似文献   

Overall indexes of coordination in front crawl swimming     

Bruno Mezêncio  João Pedro Pinho  Rudolf Huebner  João Paulo Vilas-Boas  Alberto Carlos Amadio  Julio Cerca Serrão 《Journal of sports sciences》2020,38(8):910-917

ABSTRACT

The aim of this study was to propose a group of parameters able to quantify not only arm coordination but also inter limb coordination. These include the well know index of coordination with the relative duration of the stroke phases and two new parameters: the Index of synchronization (Ids) between arms and legs actions; and the Index of inter limb coordination (IdIC) calculated as the relative foot position during successive arm stroke phases. These parameters were compared between experts and amateur swimmers in a maximal front crawl sprint. The influence of arm stroke in leg kick parameters was also assessed, comparing the full stroke condition with a condition without arms actions. Sixty-five per cent of expert swimmers used synchronized limb actions while 95% of amateur swimmers used non-synchronized limb motions. These synchronized expert swimmers also converged towards a specific coordination pattern between foot position and arm stroke phases. In the condition without arms, both groups changed kick rate and amplitude. The present study reveals the interdependency of arms and legs actions and the importance of coordination and synchronization between limbs. Therefore, the proposed group of overall indexes of coordination provides a more complete marker for the analysis of swimming technique.  相似文献   

Programming Pluralism: Using Learning Analytics to Detect Patterns in the Learning of Computer Programming     

Paulo Blikstein  Marcelo Worsley  Chris Piech  Mehran Sahami  Steven Cooper  Daphne Koller 《学习科学杂志》2013,22(4):561-599

New high-frequency, automated data collection and analysis algorithms could offer new insights into complex learning processes, especially for tasks in which students have opportunities to generate unique open-ended artifacts such as computer programs. These approaches should be particularly useful because the need for scalable project-based and student-centered learning is growing considerably. In this article, we present studies focused on how students learn computer programming, based on data drawn from 154,000 code snapshots of computer programs under development by approximately 370 students enrolled in an introductory undergraduate programming course. We use methods from machine learning to discover patterns in the data and try to predict final exam grades. We begin with a set of exploratory experiments that use fully automated techniques to investigate how much students change their programming behavior throughout all assignments in the course. The results show that students’ change in programming patterns is only weakly predictive of course performance. We subsequently hone in on 1 single assignment, trying to map students’ learning process and trajectories and automatically identify productive and unproductive (sink) states within these trajectories. Results show that our process-based metric has better predictive power for final exams than the midterm grades. We conclude with recommendations about the use of such methods for assessment, real-time feedback, and course improvement.  相似文献   

An integrated approach to develop professional and technical skills for informatics engineering students     

João M. Fernandes  Natascha van Hattum-Janssen  António Nestor Ribeiro  Victor Fonte  Luís Paulo Santos  Pedro Sousa 《European Journal of Engineering Education》2012,37(2):167-177

Many of the current approaches used in teaching and learning in engineering education are not the most appropriate to prepare students for the challenges they will face in their professional careers. The active involvement of students in their learning process facilitates the development of the technical and professional competencies they need as professionals. This article describes the organisation and impact of a mini-conference and project work – the creation of a software product and its introduction in the market – aimed at the development of professional competencies in general and writing skills in particular. The course was evaluated by assessing the students’ perception of the development of a number of professional competencies through a questionnaire completed by 125 students from two consecutive year groups. The results indicate that the project work and the mini-conference had a positive impact on students’ perceptions of the development of professional competencies.  相似文献   

PART III: KINANTHROPOMETRY     

Ricardo Dantas de Lucas  Fabrizio Caputo  Kristopher Mendes de Souza  AndrÉ Roberto Sigwalt  Karina Ghisoni  Paulo Cesar Lock Silveira 《Journal of sports sciences》2013,31(1):22-27

Whole-body bone mineral density and bone mineral mass in young adult rugby union players.  相似文献   

The acute effects of static stretching on peak force,peak rate of force development and muscle activity during single- and multiple-joint actions in older women     

Raquel Gonçalves  André Luiz Demantova Gurjão  José Claudio Jambassi Filho  Paulo De Tarso Veras Farinatti  Lilian Teresa Bucken Gobbi  Sebastião Gobbi 《Journal of sports sciences》2013,31(7):690-698

Abstract

The present study investigated the acute effects of static stretching on peak force, peak rate of force development and integrated electromyography (iEMG) in 27 older women (65 ± 4 years; 69 ± 9 kg; 157 ± 1 cm; 28 ± 4 kg · m^?2). The participants were tested during two exercises (leg press and knee extension) after two conditions: stretching and control. The data were collected on four days (counterbalanced with a 24-hour rest period). In the stretching condition, the quadriceps muscle was stretched (knee flexion) for three sets of 30 s with 30 s rest intervals. No significant difference was detected for peak force and peak rate of force development during the single- and multiple-joint exercises, regardless of the following interactions: condition (stretching and control) vs. time (pre x post x 10 x 20 x 30 minutes post; P > 0.05) and exercise vs. time (P > 0.05). Additionally, no significant interaction was found for the iEMG activity (condition vs. time; P > 0.05) in the single- and multiple-joint exercises. In conclusion, a small amount of stretching of an agonist muscle (quadriceps) did not affect the peak force, peak rate of force development and EMG activity in older women during single- and multiple-joint exercises.  相似文献   

Validity and reliability of a 6-a-side small-sided game as an indicator of match-related physical performance in elite youth Brazilian soccer players     

Rodrigo Aquino  Bruno Melli-Neto  João Victor S. Ferrari  Bruno L. S. Bedo  Luiz H. Palucci Vieira  Paulo Roberto P. Santiago 《Journal of sports sciences》2013,31(23):2639-2644

ABSTRACT

The aims of this study were: (i) to compare the external and internal load during a 6-a-side small-sided game (6v6-SSG) according to age-group; (ii) to relate these parameters between the 6v6-SSG and official matches; and (iii) to test the reliability of the 6v6-SSG. A total of 51 Brazilian youth soccer players participated in this study (U11 [n = 16]; U13 [n = 10]; U15 [n = 9]; U17 [n = 8]; U20 [n = 8]). Three experiments were conducted. Experiment A: fifty-one U11 to U20 players were submitted to 6v6-SSGs (n = 10 games; two for each age-group). Experiment B: thirty-two players were randomized to also play official matches (n = 6 matches). Experiment C: thirty-five youth players played the 6v6-SSG twice for test and retest reliability analysis. External load was obtained using Global Positioning Systems and the internal load parameter was calculated through mean heart rate. Statistical approaches showed progressive increases in all parameters according to categories (U11< U13< U15< U17< U20; p < 0.05; ES = 0.42?23.68). Even controlling for chronological age, all parameters showed likely to almost certain correlations between 6v6-SSG and official matches (r = 0.25?0.92). Collectively, the proposed protocol indicates good reliability (CV% = 2.0?12.6; TE% = 2.3?2.7%; ICC = 0.78?0.90). This research suggests that the 6v6-SSG is an alternative tool to indicate match-related physical performance in youth soccer players.  相似文献   

A linear optimization approach to the combined production planning model     

Maria Cristina N. Gramani  Paulo M. França  Marcos N. Arenales 《Journal of The Franklin Institute》2011,348(7):1523-1536

Two fundamental processes usually arise in the production planning of many industries. The first one consists of deciding how many final products of each type have to be produced in each period of a planning horizon, the well-known lot sizing problem. The other process consists of cutting raw materials in stock in order to produce smaller parts used in the assembly of final products, the well-studied cutting stock problem. In this paper the decision variables of these two problems are dependent of each other in order to obtain a global optimum solution. Setups that are typically present in lot sizing problems are relaxed together with integer frequencies of cutting patterns in the cutting problem. Therefore, a large scale linear optimizations problem arises, which is exactly solved by a column generated technique. It is worth noting that this new combined problem still takes the trade-off between storage costs (for final products and the parts) and trim losses (in the cutting process). We present some sets of computational tests, analyzed over three different scenarios. These results show that, by combining the problems and using an exact method, it is possible to obtain significant gains when compared to the usual industrial practice, which solve them in sequence.  相似文献   

Understanding the limits of Marxist approaches to sociocultural studies of science education     

Paulo Lima Junior  Fernanda Ostermann  Flavia Rezende 《Cultural Studies of Science Education》2014,9(3):591-597

In the first three sections of this paper we comment on some of the ideas developed in the forum papers, pointing out possible misunderstandings and constructing new explanations that clarify arguments we made in the original article. In the last section we expand the discussion raised in the original paper, elaborating on the limits of the use of Marxist approaches to sociocultural studies of science education. Following insights suggested by Loxley et al. (Cult Stud Sci Edu. doi:10.1007/s11422-013-9554-z, 2013) and detailed by Zuss (Cult Stud Sci Edu, 2014) on the commodification of knowledge, we sketch an analysis of how knowledge is transformed into capital to understand why contemporary scholars are likely to be engaged in a relation of production that resembles capitalist exploitation.  相似文献