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An Action-Research (AR) design was implemented throughout a competitive season in which Constraint-led and Step-Game approaches were combined. This intervention study investigated the impact of increased performance complexity on emergence of counterattacking synchronisation tendencies in team players (laterally and longitudinally on court) at different set moments. Fifteen youth volleyball team players were studied across three action-research cycles, with performance in one competitive match analysed per cycle. Team synchronisation tendencies were assessed using the cluster phase method, with a 3 (matches) x 2 (set moments) x 2 (court direction) repeated-measures ANOVA statistical procedure to calculate differences in cluster amplitude mean values. Results revealed a reduction in team synchrony levels when tactical complexity of counterattacking play increased (second AR-cycle). Nevertheless, similar levels of team synchrony emerged between the first and third AR-cycles. Results also revealed the final moments of a set as a significant environmental constraint that shaped synchronisation tendencies. Evidence suggested that the (re)achievement of functional synchrony was realised through integration of Constraint-led and Step-Game approaches during practices designed to enhance tactical awareness in players. Finally, an insider action-research design provided relevant contextualised insights on the development of a team's synchronisation tendencies.
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Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Voleibol/fisiologia , Adolescente , Feminino , Humanos , Análise e Desempenho de Tarefas , Esportes de EquipeRESUMO
RATIONALE: Adiponectin has anti-inflammatory effects in experimental models, but its role in the regulation of myocardial redox state in humans is unknown. Although adiponectin is released from epicardial adipose tissue (EpAT), it is unclear whether it exerts any paracrine effects on the human myocardium. OBJECTIVE: To explore the cross talk between EpAT-derived adiponectin and myocardial redox state in the human heart. METHODS AND RESULTS: EpAT and atrial myocardium were obtained from 306 patients undergoing coronary artery bypass grafting. Functional genetic polymorphisms that increase ADIPOQ expression (encoding adiponectin) led to reduced myocardial nicotinamide adenine dinucleotide phosphate oxidase-derived O2 (-), whereas circulating adiponectin and ADIPOQ expression in EpAT were associated with elevated myocardial O2 (-). In human atrial tissue, we demonstrated that adiponectin suppresses myocardial nicotinamide adenine dinucleotide phosphate oxidase activity, by preventing AMP kinase-mediated translocation of Rac1 and p47(phox) from the cytosol to the membranes. Induction of O2 (-) production in H9C2 cardiac myocytes led to the release of a transferable factor able to induce peroxisome proliferator-activated receptor-γ-mediated upregulation of ADIPOQ expression in cocultured EpAT. Using a NOX2 transgenic mouse and a pig model of rapid atrial pacing, we found that oxidation products (such as 4-hydroxynonenal) released from the heart trigger peroxisome proliferator-activated receptor-γ-mediated upregulation of ADIPOQ in EpAT. CONCLUSIONS: We demonstrate for the first time in humans that adiponectin directly decreases myocardial nicotinamide adenine dinucleotide phosphate oxidase activity via endocrine or paracrine effects. Adiponectin expression in EpAT is controlled by paracrine effects of oxidation products released from the heart. These effects constitute a novel defense mechanism of the heart against myocardial oxidative stress.
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Adiponectina/biossíntese , Tecido Adiposo/metabolismo , Miocárdio/metabolismo , PPAR gama/biossíntese , Pericárdio/metabolismo , Tecido Adiposo/citologia , Animais , Linhagem Celular , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Miocárdio/citologia , Técnicas de Cultura de Órgãos , Oxirredução , Pericárdio/citologia , Ratos , SuínosRESUMO
OBJECTIVE: To create a model of atherosclerosis using green fluorescent protein (GFP)-targeted monocytes/macrophages, allowing analysis of both endogenous GFP+ and adoptively transferred GFP+ myeloid cells in arterial inflammation. APPROACH AND RESULTS: hCD68GFP reporter mice were crossed with ApoE-/- mice. Expression of GFP was localized to macrophages in atherosclerotic plaques and in angiotensin II-induced aortic aneurysms and correlated with galectin 3 and mCD68 expression. Flow cytometry confirmed GFP+ expression in CD11b+/CD64+, CD11c+/MHC-IIHI, and CD11b+/F4/80+ myeloid cells. Adoptive transfer of GFP+ monocytes demonstrated monocyte recruitment to both adventitia and atherosclerotic plaque, throughout the aortic root, within 72 hours. We demonstrated the biological utility of hCD68GFP monocytes by comparing the recruitment of wild-type and CCR2-/- monocytes to sites of inflammation. CONCLUSIONS: hCD68GFP/ApoE-/- mice provide a new approach to study macrophage accumulation in atherosclerotic plaque progression and to identify cells recruited from adoptively transferred monocytes.
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Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Aorta/metabolismo , Doenças da Aorta/metabolismo , Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo , Placa Aterosclerótica , Transferência Adotiva , Angiotensina II , Animais , Antígenos CD/genética , Antígenos de Diferenciação/metabolismo , Antígenos de Diferenciação Mielomonocítica/genética , Aorta/patologia , Aneurisma Aórtico/induzido quimicamente , Aneurisma Aórtico/genética , Aneurisma Aórtico/metabolismo , Aneurisma Aórtico/patologia , Doenças da Aorta/genética , Doenças da Aorta/patologia , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/patologia , Antígeno CD11b/metabolismo , Antígeno CD11c/metabolismo , Rastreamento de Células/métodos , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Galectina 3/metabolismo , Predisposição Genética para Doença , Proteínas de Fluorescência Verde/genética , Macrófagos/patologia , Macrófagos/transplante , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/patologia , Monócitos/transplante , Fenótipo , Receptores de IgG/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transdução de SinaisRESUMO
Contextual influences on talent development (e.g., birthplace effects) have become a topic of interest for sport scientists. Birthplace effects occur when being born in a certain city size leads to participation or performance advantages, typically for those born in smaller or mid-sized cities. The purpose of this study was to investigate birthplace effects in Portuguese volleyball players by analysing city size, as well as population density - an important but infrequently used variable. Participants included 4062 volleyball players (Mage = 33), 53.2% of whom were men. Using Portuguese national census data from 1981, we compared participants (within each sex) across five population categories. In addition, we used ANOVAs to study expertise and population density. Results indicated that men and women athletes born in districts of 200,000-399,999 were 2.4 times more likely to attain elite volleyball status, while all other districts decreased the odds of expert development. For men, being born in high-density areas resulted in less chance of achieving expertise, whereas there were no differences for women. The results suggest that athletes' infrastructure and social structure play an important role in talent development, and that these structures are influenced by total population and population density, respectively.
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Aptidão , Densidade Demográfica , Características de Residência , Voleibol , Adulto , Desempenho Atlético , Cidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Adulto JovemRESUMO
OBJECTIVE: To explore the role of systemic inflammation in the regulation of adiponectin levels in patients with ischemic heart disease. APPROACH AND RESULTS: In a cross-sectional study of 575 subjects, serum adiponectin was compared between healthy subjects, patients with coronary artery disease with no/mild/severe heart failure (HF), and patients with nonischemic HF. Adiponectin expression and release from femoral, subcutaneous and thoracic adipose tissue was determined in 258 additional patients with coronary artery bypass grafting. Responsiveness of the various human adipose tissue depots to interleukin-6, tumor necrosis factor-α, and brain natriuretic peptide (BNP) was examined by using ex vivo models of human fat. The effects of inducible low-grade inflammation were tested by using the model of Salmonella typhi vaccine-induced inflammation in healthy individuals. In the cross-sectional study, HF strikingly increased adiponectin levels. Plasma BNP was the strongest predictor of circulating adiponectin and its release from all adipose tissue depots in patients with coronary artery bypass grafting, even in the absence of HF. Femoral AT was the depot with the least macrophages infiltration and the largest adipocyte cell size and the only responsive to systemic and ex vivo proinflammatory stimulation (effect reversible by BNP). Low-grade inflammation reduced circulating adiponectin levels, while circulating BNP remained unchanged. CONCLUSIONS: This study demonstrates the regional variability in the responsiveness of human adipose tissue to systemic inflammation and suggests that BNP (not systemic inflammation) is the main driver of circulating adiponectin in patients with advanced atherosclerosis even in the absence of HF. Any interpretation of circulating adiponectin as a biomarker should take into account the underlying disease state, background inflammation, and BNP levels.
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Adiponectina/biossíntese , Tecido Adiposo/metabolismo , Insuficiência Cardíaca/metabolismo , Inflamação/metabolismo , Isquemia Miocárdica/metabolismo , Peptídeo Natriurético Encefálico/fisiologia , Adiponectina/genética , Idoso , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/fisiopatologia , Ponte de Artéria Coronária , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/metabolismo , Estudos Transversais , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Interleucina-6/sangue , Interleucina-6/farmacologia , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Peptídeo Natriurético Encefálico/sangue , Técnicas de Cultura de Órgãos , Especificidade de Órgãos , Fatores de Risco , Gordura Subcutânea , Coxa da Perna , Tórax , Fator de Necrose Tumoral alfa/farmacologia , Ultrassonografia , Vasodilatação , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
This study aimed to examine the indirect teaching strategies adopted by a coach educator in terms of promoting student-coaches' engagement in a positive and active learning environment. The participants were an expert coach educator and seven student-coaches from an academic coaching setting. A mix method approach was used to collect data. Whilst video-recording and participant observations were used to collect data from the lessons, focus groups were adopted to recall the perceptions of student-coaches. The results showed that indirect teaching strategies (i.e., asking questions, showing signs of autonomy by monitoring the pace at which they completed tasks and actively engaging in the search for solutions to tasks) implemented by the coach educator promoted a supportive and challenging learning environment which, in turn, encouraged student-coaches to be more actively involved in the lessons. Additionally, the affective aspects of the relationship established with student-coaches (tone of voice, gestures, facial expressions, eye contact, physical contact and humor) led them to feel confident in exposing their doubts and opinions, and in learning in a more autonomous manner. Moreover, the practical lessons proved to be crucial in helping student-coaches to reach broader and deeper forms of understanding by allowing the application of theory to coaching practice. In conclusion, this study reinforces the value of indirect teaching strategies to stimulate an active learning environment. It further highlights the value of practical learning environments to better prepare neophyte coaches for dealing with the complex and dynamic nature of their professional reality. Key pointsBoth instructional and affective teaching indirect strategies used by the coach educator promoted a positive and challenging learning environment to student-coaches.The directness profile used by this coach educator (questioning, giving autonomy for problem solving and responsibility to regulate the learning tasks development) promoted the awareness and the ability of student-coaches to explore alternative solutions and self-regulate their own learning.Using humor, touch, gestures and tone of voice, the coach educator showed great care for student-coaches, which impacted positively on their enthusiasm, confidence and desire to be actively engaged in their own learning.
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BACKGROUND: Adiponectin is an adipokine with potentially important roles in human cardiovascular disease states. We studied the role of adiponectin in the cross-talk between adipose tissue and vascular redox state in patients with atherosclerosis. METHODS AND RESULTS: The study included 677 patients undergoing coronary artery bypass graft surgery. Endothelial function was evaluated by flow-mediated dilation of the brachial artery in vivo and by vasomotor studies in saphenous vein segments ex vivo. Vascular superoxide (O2(-)) and endothelial nitric oxide synthase (eNOS) uncoupling were quantified in saphenous vein and internal mammary artery segments. Local adiponectin gene expression and ex vivo release were quantified in perivascular (saphenous vein and internal mammary artery) subcutaneous and mesothoracic adipose tissue from 248 patients. Circulating adiponectin was independently associated with nitric oxide bioavailability and O2(-) production/eNOS uncoupling in both arteries and veins. These findings were supported by a similar association between functional polymorphisms in the adiponectin gene and vascular redox state. In contrast, local adiponectin gene expression/release in perivascular adipose tissue was positively correlated with O2(-) and eNOS uncoupling in the underlying vessels. In ex vivo experiments with human saphenous veins and internal mammary arteries, adiponectin induced Akt-mediated eNOS phosphorylation and increased tetrahydrobiopterin bioavailability, improving eNOS coupling. In ex vivo experiments with human saphenous veins/internal mammary arteries and adipose tissue, we demonstrated that peroxidation products produced in the vascular wall (ie, 4-hydroxynonenal) upregulate adiponectin gene expression in perivascular adipose tissue via a peroxisome proliferator-activated receptor-γ-dependent mechanism. CONCLUSIONS: We demonstrate for the first time that adiponectin improves the redox state in human vessels by restoring eNOS coupling, and we identify a novel role of vascular oxidative stress in the regulation of adiponectin expression in human perivascular adipose tissue.
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Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Doença da Artéria Coronariana/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Adiponectina/genética , Idoso , Aldeídos/metabolismo , Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Feminino , Expressão Gênica/fisiologia , Humanos , Masculino , Artéria Torácica Interna/metabolismo , Artéria Torácica Interna/transplante , Óxido Nítrico/metabolismo , Oxirredução , Estresse Oxidativo/fisiologia , PPAR gama/metabolismo , Veia Safena/metabolismo , Veia Safena/transplante , Superóxidos/metabolismo , Vasodilatação/fisiologiaRESUMO
Background: Deep brain stimulation (DBS) can be an effective therapy to control motor signs in patients with Parkinson's disease (PD). However, subthalamic nucleus (STN) DBS can induce undesirable psychiatric adverse effects, including elevated mood. Case report: We reported a video case of a 73-year-old male implanted with bilateral STN DBS who experienced stimulation-induced elevated mood. A correlation between mood changes and enhanced activation of the ventromedial region in the left STN was observed. Discussion: This video case report illustrates STN DBS-induced elevated mood and enhances early symptom recognition for patients and diagnostic awareness for professionals.
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Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Estimulação Encefálica Profunda/efeitos adversos , Masculino , Núcleo Subtalâmico/fisiopatologia , Idoso , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Gravação em VídeoRESUMO
Purpose: Although emerging research has explored the development of coach education curricula, coach learning and how a deep learning approach can be made accessible to aspiring coaches, the study of coach educators' scaffolding of micro-pedagogies in action remains a missing link in the field. Therefore, the purpose of this study was to explore scaffolding strategies adopted by an experienced coach educator to encourage aspiring coaches to adopt an active approach to learning. Method: A case-study was conducted for a full semester of twelve practical lessons in the unit "Sports Methodology I-Volleyball" of a renowned sport sciences coach education program. Multiple data collection sources included participant observation, video and audio recordings, individual interviews with the coach educator and focus group interviews with the aspiring coaches. A thematic analysis was performed, and trustworthiness criteria included data triangulation, crosschecking, and collaborative interpretational analysis. Results: The strategies adopted by the coach educator progressively unfolded throughout three main stages: (i) laying the foundations of a learner-oriented approach; (ii) enhancing personally meaningful learning experiences; and (iii) mediating peer-coaching activities. An intricate interplay was unraveled between the nature and reduction of the support given and the increased responsibility transferred to the aspiring coaches for their active participation in learning experiences. Conclusions: The learner-oriented scaffolding processes employed by the coach educator sought to promote enhanced understanding of game-play problem-solving and the aspiring coaches' development of a deeper sense of what is required to become a coach through engagement in coaching technical activities and peer-coaching interventions.
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Tutoria , Voleibol , Humanos , Escolaridade , Currículo , Grupos FocaisRESUMO
This study characterised the sport participation patterns of 546 male youth team sport players. A retrospective questionnaire was used to identify the sport starting age (general sports and main sport) and the quantity and type of sports undertaken during the early years of development. A mixed-ANOVA and Chi-square tests were implemented. All participants started involvement in sports at the same age (~5 years) and participated in the same number of sports during their early years (1 to 2 sports). However, football players started participating mainly in team games (football, futsal) and water polo players in CGS sports (swimming). Participants reported different ages for initial participation in: (i) main sport (football players started participating earlier, around 5-6 years), (ii) onset of specialisation (football players specialised earlier, around 7 or 8 years), (iii) types of sports engaged in (football players were involved in more team games and water polo in more CGS sports), and (iv) variations in weekly training hours (water polo reported more hours of training). This study provided empirical evidence for understanding the effects of different sporting pathways on long-term athlete development. Some key incongruities between contemporary knowledge and practice are acknowledged. Further investigations should be developed by examining the trajectories in different sports, countries, genders, and cultural contexts.
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Combining Constraint-led (ecological) and Step-Game (constructivist) approaches through an Action-Research (AR) design conducted throughout a competitive volleyball season, this study aimed to: (i) analyse the impact of increased tactical complexity on lateral and longitudinal collective Synchronisation Tendencies (ST) during defensive and offensive counterattack-subphases, and (ii) examine how opposition attacking contexts (i.e. playing in full-system or in-system) might influence ST throughout each counterattack-subphase. Performance of a youth team, comprised of 15 players, was studied across three AR-cycles. The team's competitive performance was analysed through three competitive matches (one per cycle). Team ST were evaluated using the cluster-phase method and a 3 (matches) × 2 (counterattack-subphases) × 2 (opposition attacking contexts) × 2 (court directions) repeated-measures ANOVA were used to calculate the differences in cluster-amplitude mean values. Results showed that increments in tactical complexity (second AR-cycle) were followed by decreases in collective ST, which were (re)achieved during the third AR-cycle, possibly due to the ecological-constructivist coaching intervention. Our findings imply that coaches could design representative and specific-didactical learning environments, predicated on a team's tactical needs and strategical ideas from a game-plan, framing player intentionality. Results also support the use of questioning strategies to narrow players' attentional focus, stimulating perceptual attunement to relevant constraints emerging in performance. Finally, the insider AR-design provided valuable contextualised insights on coaching interventions for developing collective coordinative structures.
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Desempenho Atlético , Tutoria , Voleibol , Adolescente , Humanos , Aprendizagem , Estações do AnoRESUMO
According to the Quality Education and Gender Equality ambitions established at the 2030 Agenda for Sustainable Development Goals, we aimed to test the feasibility of a flexible planning and assessment process, using ongoing, bidirectional feedback between planning and assessment. Eighteen players (11.5 ± 0.5 years of age) from a U13 female volleyball team were randomized into an experimental group (in which the plan could be changed daily) or a contrast group (pre-defined planning, adjusted monthly). The pedagogical intervention lasted three months. Besides ongoing daily assessments from the training practices, the Game Performance Assessment Instrument was adopted as a starting point for the weekly assessments in 4 vs. 4 game-forms (i.e., the instrument was modified monthly based on feedback from the training process). Information from daily and weekly formal assessment was used in the planning of the experimental group, and monthly in the contrast group. Data suggested that pre-established and strict planning (even updated monthly) failed to fit current learner needs. Over 12 weeks, the pre-established planning suffered regular modifications in the experimental group, and the assessment tool changed monthly. In conclusion, both planning and assessment should be open and flexible to exchange information mutually, and support the design of tailor-made learning environments.
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Quality in education is one of the 17 goals in the United Nations' sustainable agenda for 2030, presupposing careful planning and assessment of learning. Traditional planning in sports education (either in training or school settings) largely adopts pre-determined learning sequences and temporal milestones that, in theory, enhance the learning process. However, learning is a context-dependent, non-linear process with considerable intra- and interindividual variability, whereby planning and assessment should also be non-linear. In this narrative review, the main findings suggest that the specific teaching or training contents and their relative (i.e., ordering or sequencing) and absolute timing (i.e., the specific time point where certain learning or adaptations are expected) should vary depending on the learners and the context. In a process-oriented perspective, this requires flexible planning and the establishment of ongoing bidirectional links between planning and assessment. In this framework, assessment should be a flexible, evolving, and daily pedagogical tool instead of a set of formal checkpoints. We further explored how planning and assessment could be linked to provide an ongoing feedback loop that respects the individuality of each learner and its context, and therefore hope this review helps bring about a change in current planning and assessment paradigms in sports education.
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Aprendizagem , Escolaridade , Retroalimentação , Estudos LongitudinaisRESUMO
CONTEXT: Aging causes a progressive worsening in postural balance, affecting functional independence and increasing the risk of falls. OBJECTIVE: The aim of the study was to evaluate the effect of aging on the static balance in women from 50-years to 89-years of age. DESIGN: This was a cross-sectional study, with 400 irregularly active women were evaluated and grouped by age: Group 6th decade (age 50 to 59) â 58 participants; Group 7th decade (age 60 to 69) â 214 participants; Group 8th decade (age 70 to 79) â 92 participants; Group 9th decade (age 80 to 89) â 36 participants. Postural balance was evaluated using a portable force platform in a standard standing position, with Eyes Open (EO) and Eyes Closed (EC). RESULTS: In the two measurement conditions, the elderly women in Group 9th decade presented mediolateral displacement and range, and mean velocity greater than the women's values in Groups 6th and 7th decade. In the EO e EC situation, the displacement was higher in the elderly Group 9th decade compared to younger groups. Group 8th has a mean velocity greater than Group 6th decade in the EO situation. CONCLUSIONS: Posturography showed a decline in postural balance with advancing age, suggesting that the 9th decade of life is a borderline age to this detriment due to an increase in postural instability.
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Acidentes por Quedas , Equilíbrio Postural , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Purpose: Using an action-research design, this study examined the impact of combining concepts from two contemporary pedagogical approaches, the Constraints-led Approach (CLA) and Step-Game Approach (SGA), on the development of youth volleyballers' tactical knowledge, as expressed in performance, throughout a full competitive season. Method: Fifteen players and one coach participated in this study, which involved three action-research cycles, each including the processes of planning, acting and monitoring, reflecting, and fact-finding. The first author, who had the role of coach-researcher, collected data using a reflexive diary and field notes between September 2017 and June 2018, as well as eight semi-structured focus-group interviews. Data were analyzed using thematic analysis, in which inductive procedures deepened understanding of the development of the participants' tactical knowledge. Results: Findings suggested that combining CLA with SGA improved tactical knowledge in specific ways. Players progressed from a starting point where they were only able to describe game scenarios, and act without tactical criteria or considering contextual game constraints, to a point where their intentions during tactical actions were shaped by their ability to think strategically and guide their attention to recognize and interpret different constraints. Conclusions: Results suggested that the development of players' tactical knowledge benefited from a mutual integration of different, yet complementary, pedagogical approaches. By integrating SGA and CLA it was possible to enhance players' adaptable thinking using learning tasks involving the manipulation of meaningful constraints that afforded variable repetition and the resolution of tactical problems.
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Desempenho Atlético , Adolescente , Grupos Focais , Humanos , Aprendizagem , Estudos LongitudinaisRESUMO
The purpose of this study was to understand the perceptions of highly skilled and less skilled volleyball players about the influences that parents, coaches, and peers had on their sport development and performance achievement. Highly skilled (n = 30) and less skilled (n = 30) volleyball players participated in semi-structured retrospective interviews to explain how parents, coaches and peers may have influenced their sport participation. Data was analyzed through a process of content analysis. Results indicated that parents, coaches, and peers had an important influence in player's sport development but differing according to players' expertise level. Concerning to parental influences, tangible support during the early years of development was mentioned by all players. However, parents' level of involvement and parenting styles revealed interesting differences between highly skilled and less skilled players. Highly skilled players perceived a moderate parental involvement and an autonomy-supportive parenting style, while less skilled players referred a excessive parental involvement in players' sport participation. Coaches influences showed to have some similarities in the early years with all players mentioning coaches as caring and recognizing their value as an athlete. However, highly skilled players described a different training environment characterized by a demanding coach, individualized instruction, and specific goal setting. Regarding peers' influence, all players recognized that friends were not only one of the main reasons to start playing volleyball, but also an important source of support to remain engaged and staying motivated to do sport. Highly skilled players, however, mentioned the importance of teammates' positive push and critiques during practice for enhancing their motivation, team cohesion and friendship. They also highlighted the importance of friends outside of sport in the later years of their career by acting as an escape from all the pressure that emerged from volleyball training and competition demands. Overall, these findings highlight different social influences according to the players' expertise level suggesting the need to examine more extensively the nature of significant others' support on athlete and talent development.
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Traditional talent identification and development programs have sought to identify and select the most promising children as athletes of the future, to provide them with specialised training and preparation for expert performance in sport from an early age. Traditional models of talent identification and development tend to be linear, emphasising the numbers of hours spent in specialised training. However, major concerns have been raised by evidence emerging on psycho-emotional and physical issues with early specialisation programmes, and negative associations with wellbeing and mental health. More contemporary models of talent development emphasise a deep integration of specialised training with more general enrichment of athleticism. This integrative process enhances self-regulation processes of perception and action, as well as emotional control and social interactions, all of which underpin sports performance at elite and sub-elite levels. Here, we discuss insights and principles of contemporary models of pedagogy, such as Nonlinear Pedagogy (NLP) and the Athletic Skills Model (ASM), which offer valuable frameworks for talent development. We conclude by considering implications of adopting such principles for developing athlete functionality in specific performance environments.
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Aptidão , Desempenho Atlético , Atletas , Criança , HumanosRESUMO
BACKGROUND: In obesity, decreases in adiponectin and increases in proinflammatory adipokines are associated with heart disease. Because adipocytes express mineralocorticoid receptor (MR) and MR blockade reduces cardiovascular inflammation and injury, we tested the hypothesis that MR blockade reduces inflammation and expression of proinflammatory cytokines in adipose tissue and increases adiponectin expression in adipose tissue and hearts of obese mice. METHODS AND RESULTS: We determined the effect of MR blockade (eplerenone, 100 mg/kg per day for 16 weeks) on gene expression in retroperitoneal adipose and heart tissue from obese, diabetic db/db mice (n=8) compared with untreated obese, diabetic db/db mice (n=10) and lean, nondiabetic db/+ littermates (n=11). Expression of tumor necrosis factor-alpha, monocyte chemoattractant protein-1, plasminogen activator inhibitor type 1, and macrophage protein CD68 increased, and expression of adiponectin and peroxisome proliferator-activated receptor-gamma decreased in retroperitoneal adipose tissue from obese versus lean mice. In addition, adiponectin expression in heart was reduced in obese versus lean mice. MR blockade prevented these obesity-related changes in gene expression. Furthermore, treatment of undifferentiated preadipocytes with aldosterone (10(-8) mol/L for 24 hours) increased mRNA levels of tumor necrosis factor-alpha and monocyte chemoattractant protein-1 and reduced mRNA and protein levels of peroxisome proliferator-activated receptor-gamma and adiponectin, supporting a direct aldosterone effect on gene expression. CONCLUSIONS: MR blockade reduced expression of proinflammatory and prothrombotic factors in adipose tissue and increased expression of adiponectin in heart and adipose tissue of obese, diabetic mice. These effects on adiponectin and adipokine gene expression may represent a novel mechanism for the cardioprotective effects of MR blockade.
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Aldosterona/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Inflamação/tratamento farmacológico , Antagonistas de Receptores de Mineralocorticoides , Obesidade/tratamento farmacológico , Células 3T3-L1 , Adipocinas/genética , Adipocinas/imunologia , Adiponectina/genética , Adiponectina/imunologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/imunologia , Animais , Biomarcadores , Peso Corporal , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/imunologia , Homeostase/imunologia , Inflamação/complicações , Inflamação/imunologia , Leptina/genética , Leptina/imunologia , Masculino , Camundongos , Camundongos Mutantes , Miocárdio/imunologia , Obesidade/complicações , Obesidade/imunologia , PPAR gama/genética , PPAR gama/imunologia , RNA Mensageiro/metabolismo , Receptores de Mineralocorticoides/metabolismo , Triglicerídeos/sangueRESUMO
Obesity is associated with changes in the secretome of adipose tissue (AT), which affects the vasculature through endocrine and paracrine mechanisms. Wingless-related integration site 5A (WNT5A) and secreted frizzled-related protein 5 (SFRP5), adipokines that regulate noncanonical Wnt signaling, are dysregulated in obesity. We hypothesized that WNT5A released from AT exerts endocrine and paracrine effects on the arterial wall through noncanonical RAC1-mediated Wnt signaling. In a cohort of 1004 humans with atherosclerosis, obesity was associated with increased WNT5A bioavailability in the circulation and the AT, higher expression of WNT5A receptors Frizzled 2 and Frizzled 5 in the human arterial wall, and increased vascular oxidative stress due to activation of NADPH oxidases. Plasma concentration of WNT5A was elevated in patients with coronary artery disease compared to matched controls and was independently associated with calcified coronary plaque progression. We further demonstrated that WNT5A induces arterial oxidative stress and redox-sensitive migration of vascular smooth muscle cells via Frizzled 2-mediated activation of a previously uncharacterized pathway involving the deubiquitinating enzyme ubiquitin-specific protease 17 (USP17) and the GTPase RAC1. Our study identifies WNT5A and its downstream vascular signaling as a link between obesity and vascular disease pathogenesis, with translational implications in humans.
Assuntos
Tecido Adiposo/metabolismo , Vasos Sanguíneos/metabolismo , Endopeptidases/metabolismo , NADPH Oxidases/metabolismo , Obesidade/metabolismo , Transdução de Sinais , Proteína Wnt-5a/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Tecido Adiposo/efeitos dos fármacos , Animais , Artérias/metabolismo , Artérias/patologia , Aterosclerose/sangue , Aterosclerose/complicações , Aterosclerose/patologia , Vasos Sanguíneos/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Ligantes , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Obesidade/complicações , Oxidantes/toxicidade , Oxirredução , Transdução de Sinais/efeitos dos fármacos , Doenças Vasculares/complicações , Doenças Vasculares/metabolismo , Proteína Wnt-5a/sangueRESUMO
Resumo A relevância do futsal brasileiro no cenário mundial é reconhecida pela sua prática massiva e conquistas internacionais. Neste contexto, compreender aspectos envoltos de uma função relevante, a de treinador, torna-se fundamental. O objetivo deste estudo foi investigar as percepções de treinadores brasileiros de elite sobre os aspectos influenciadores na escolha da profissão e os conhecimentos fundamentais necessários à competência profissional. Realizaram-se entrevistas em profundidade com 10 treinadores de elite. Os resultados sugerem que a influência familiar, a exposição prolongada à prática, à escola e aos seus treinadores enquanto atletas foram fundamentais nas suas trajetórias. O conhecimento específico do futsal, a leitura de jogo e a tomada de decisão parecem ser relevantes para a competência na função. Por fim, a relação aberta, de troca e cobrança com os atletas demonstram ser essenciais no contexto prático e a busca pelo desenvolvimento dos atletas é realizada de maneira global.
Abstract The growing worldwide significance of Brazilian futsal is recognized due to its extensive practice and international achievements. In this context, it becomes essential to further explore the critical aspects associated with the coaching role. The aim of this study was to investigate elite Brazilian coaches' perceptions regarding the factors influencing their decision to pursue this profession and the fundamental aspects related to coaches' professional competence. In-depth interviews were conducted with 10 elite coaches. The results suggest that family influence, prolonged exposure to practice, the school, and their coaches were fundamental in shaping the coaches' professional trajectories. Specific futsal knowledge, game reading, and decision making seem to be relevant for competence in the role. Finally, an open, reciprocal, and accountable relationship with athletes is considered essential in the practical context, as well as the pursuit of significantly contributing to athlete development as an integral part of the coaching role.
Resumen La importancia del fútbol sala brasileño es mundialmente reconocida por su práctica masiva y logros internacionales. En este contexto, es fundamental profundizar en la comprensión de los aspectos críticos involucrados en el rol del entrenador. El objetivo de este estudio fue investigar las percepciones de entrenadores de élite brasileños sobre los aspectos que influyen en la elección de la profesión y los conocimientos fundamentales necesarios para la competencia profesional. Se realizaron entrevistas en profundidad a 10 entrenadores de élite. Los resultados sugieren que la influencia familiar, la exposición prolongada a la práctica, la escuela y sus entrenadores como atletas fueron fundamentales en sus trayectorias. El conocimiento específico del fútbol sala, la lectura de juegos y la toma de decisiones parecen ser relevantes para la competencia en el rol. Finalmente, la relación abierta, de intercambio y de rendición de cuentas con los atletas resultan esenciales en la práctica y que la búsqueda del desarrollo de los atletas se realice de manera global.