Application of velocity loss thresholds during free-weight resistance training: Responses and reproducibility of perceptual,metabolic, and neuromuscular outcomes     

Jonathon Weakley  Shaun McLaren  Carlos Ramirez-Lopez  Amador García-Ramos  Nick Dalton-Barron  Harry Banyard 《Journal of sports sciences》2020,38(5):477-485

ABSTRACT

The aim of this study was to investigate the differences and long-term reliability in perceptual, metabolic, and neuromuscular responses to velocity loss resistance training protocols. Using a repeated, counterbalanced, crossover design, twelve team-sport athletes completed 5-sets of barbell back-squats at a load corresponding to a mean concentric velocity of ~0.70 m·s^?1. On different days, repetitions were performed until a 10%, 20% or 30% velocity loss was attained, with outcome measures collected after each set. Sessions were repeated after four-weeks. There were substantial between-protocol differences in post-set differential ratings of perceived exertion (dRPE, i.e., breathlessness and leg muscles, AU) and blood lactate concentration (B[La], mmol·L^?1), such that 30%>20%>10% by small to large magnitudes. Differences in post-set countermovement jump (CMJ) variables were small for most variables, such that 30%<20%<10%. Standard deviations representing four-week variability of post-set responses to each protocol were: dRPE, 8–11; B[La], 0.8–1.0; CMJ height, 1.6–2.0; CMJ PPO, 1.0–1.8; CMJ PCV, 0.04–0.06; CMJ 100ms-Impulse, 5.7–11.9. Velocity loss thresholds control the magnitude of perceptual, metabolic, and neuromuscular responses to resistance training. For practitioners wanting to reliably prescribe training that can induce a given perceptual, metabolic, or neuromuscular response, it is strongly advised that velocity-based thresholds are implemented.  相似文献   

The load-velocity profile differs more between men and women than between individuals with different strength levels     

Alejandro Torrejón  Carlos Balsalobre-Fernández  G. Gregory Haff 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(3):245-255

This study aimed to determine the suitability of the load-velocity relationship to prescribe the relative load (%1RM) in women, as well as to compare the load-velocity profile between sexes and participants with different strength levels. The load-velocity relationship of 14 men (1RM: 1.17 ± 0.19) and 14 women (1RM: 0.66 ± 0.13) were evaluated in the bench press exercise. The main findings revealed that: (I) the load-velocity relationship was always strong and linear (R² range: 0.987–0.993), (II) a steeper load-velocity profile was observed in men compared to women (Effect size [ES]: 1.09), with men showing higher velocities for light loads (ES: ? 0.81 and ? 0.40 for the y-intercept and 30%1RM, respectively), but women reporting higher velocities for the heavy loads (ES: 1.14 and 1.50 at 90%1RM and 100%1RM, respectively); and (III) while the slope of the load-velocity profile was moderately steeper for weak men compared to their strong counterpart (ES: 1.02), small differences were observed between strong and weak women (ES: ? 0.39). While these results support the use of the individual load-velocity relationship to prescribe the %1RM in the bench press exercise for women, they also highlight the large disparities in their load-velocity profile compared to men.  相似文献   

Trajectories of Adjustment in a Brazilian Sample of Street-Involved Youth     

Rebeca Fernandes Ferreira Lima  Marcela Raffaelli  Normanda Araujo de Morais  Juliana P. Santana  Carlos J. Nieto  Silvia H. Koller 《Child development》2020,91(4):1237-1253

Trajectories of adjustment were examined in a sample of street-involved youth across a 1-year period. Participants (N = 113; M_age = 14.18 years; 80.5% male, 91% non-White) were recruited in three Brazilian cities. Interviews conducted at three time points included six measures of physical and psychological adjustment. Unconditional growth models revealed linear declines over time (i.e., improved adjustment) on three indicators: health symptoms, sexual risk behaviors, and negative affect. There were no linear changes in drug use, positive affect, or life satisfaction. Conditional growth models revealed few significant effects for age or gender, but ratings of stressful life events moderated longitudinal changes in health symptoms, drug use, and negative affect. Implications for practice, policy, and theory are discussed.  相似文献   

Aerobic fitness and physical activity are inversely associated with body fat,dyslipidemia and inflammatory mediators in children and adolescents living with HIV     

Luiz Rodrigo Augustemak de Lima  Isabela de Carlos Back  Everson Araújo Nunes  Diego Augusto Santos Silva  Edio Luiz Petroski 《Journal of sports sciences》2019,37(1):50-58

This study aimed to investigate if moderate to vigorous physical activity (MVPA) and aerobic fitness are associated with cardiovascular risk factors in HIV+ children and adolescents. Sixty-five children and adolescents (8 to 15 years) provided minutes of MVPA measured by accelerometers and peak oxygen uptake (peak VO₂) by breath-by-breath respiratory exchange. Cardiovascular risk factors were characterized by body fat, blood pressure, total cholesterol, HDL-c, LDL-c, triglycerides, glucose, insulin, C-reactive protein (CRP), interleukin (IL)-6, tumor necrosis factor-alpha (TNF-α) and carotid intima-media thickness. Results indicated that higher MVPA was associated with lower values of total (β = ?3.566) and trunk body fat (β = ?3.495), total cholesterol (β = ?0.112) and LDL-c (β = ?0.830). Likewise, higher peak VO₂ was associated with lower total (β = ?0.629) and trunk body fat values (β = ?0.592) and levels of CRP (β = ?0.059). The physically active participants had lower total cholesterol (?24.4 mg.dL^?1) and LDL-c (?20.1 mg.dL^?1) compared to participants judged to be insufficiently active. Moreover, participants with satisfactory peak VO? showed lower total (?4.1%) and trunk (?4.3%) body fat, CRP (?2.3 mg.L^?1), IL-6 (?2.4 pg.mL^?1) and TNF-α (?1.0 pg.mL^?1) compared to low peak VO₂ peers. High levels of MVPA and aerobic fitness may prevent developing of cardiovascular risk factors in children and adolescents HIV+.  相似文献   

A multi-nation examination of the fatigue and recovery time course during the inaugural Under-18 Six Nations rugby union competition     

Carlos Ramírez-López  Kevin Till  Thomas Sawczuk  Pierosario Giuliano  Alexis Peeters  Grant Beasley 《Journal of sports sciences》2020,38(6):644-651

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The institution of institutionalism: difference,universalism and the legacies of Institutional Critique     

Carlos Garrido Castellano 《Culture, Theory & Critique》2018,59(1):59-73

This text analyses the relationship between institutionalism, context and cultural criticism. Its main objective is to identify how universalism has permeated the different waves of Institutional Critique, conditioning the subversive potential conferred to creative practices and locating radical, alternative institutionalism within the narrow geo-cultural landscape of mainstream biennials. Taking as point of departure Cildo Meireles’s participatory public intervention in documenta 11, I consider how representational concerns are privileged vis-à-vis visual practices related to coloniality and difference. From that position, the article argues that only by challenging the assumed universality of the debates on cultural institutionalism will we be able to stress the relevance of critique in addressing cultural policies and non-representational practices. This implies confronting the troublesome relationship between Institutional Critique and modernity from a ‘geographically-informed’ position capable of recognising institutionalism as a heterogeneous body of practices that are being globally transformed.  相似文献   

Relations among positive parenting, children's effortful control, and externalizing problems: a three-wave longitudinal study     

Eisenberg N  Zhou Q  Spinrad TL  Valiente C  Fabes RA  Liew J 《Child development》2005,76(5):1055-1071

In a 3-wave longitudinal study (with assessments 2 years apart) involving 186 early adolescents (M ages of approximately 9.3, 11.4, and 13.4), the hypothesis that parental warmth/positive expressivity predicts children's effortful control (EC) (a temperamental characteristic contributing to emotion regulation) 2 years later, which in turn predicts low levels of externalizing problems another 2 years later, was examined. The hypothesis that children's EC predicts parenting over time was also examined. Parents were observed interacting with their children; parents and teachers reported children's EC and externalizing problems; and children's persistence was assessed behaviorally. Children's EC mediated the relation between positive parenting and low levels of externalizing problems (whereas there was no evidence that children's EC predicted parenting).  相似文献   

Students with special educational needs and cooperative learning in the ordinary classroom: some learnings from teaching practice     

Ignacio Perlado Lamo de Espinosa  Yolanda Muñoz Martínez  Juan Carlos Torrego Seijo 《Journal of Research in Special Educational Needs》2021,21(3):211-221

This article presents the results of a study to determine the strategies used by teachers to include students with special educational needs in regular classrooms, primarily using Cooperative Learning strategies. It aims to identify the factors of inclusive learning in order to enhance the participation and learning of all students in the classroom and in their cooperative teams. A qualitative case study was carried out in the context of the teachers participating in a postgraduate course ‘expert in cooperative learning’ offered by the University of Alcalá (Spain), over a period of six years (2011–2017), involving the participation of 176 professional teachers. All the participants attended an annual university continuous training course on cooperative learning. Document analysis, in-depth interviews and a questionnaire designed ad hoc were used. The conclusions include the importance of cooperative work in facilitating inclusive education, with a variety of different strategies used to respond to all students' needs, and those with special educational needs in particular, and the coordination required between teachers and special educational needs specialists to implement those strategies.  相似文献   

Curriculum-Integrated Information Literacy (CIIL) in a Community College Nursing Program: A Practical Model     

Carlos Argüelles 《Community College Journal of Research & Practice》2016,40(11):942-953

This article describes a strategy to integrate information literacy into the curriculum of a nursing program in a community college. The model is articulated in four explained phases: preparatory, planning, implementation, and evaluation. It describes a collaborative process encouraging librarians to work with nursing faculty, driving students to acquire information literacy competencies, to use information resources as part of their learning process, and to be lifelong learners. The literature reviews the evolution of the concept of informatics in nursing practice and the different blueprints organized to attain information literacy competencies. It also describes studies that have included these competencies into nursing curriculum.  相似文献   

Review symposium     

Crain Soudien  Carlos Alberto Torres 《British Journal of Sociology of Education》2008,29(6):719-725

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