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Several studies have investigated biomechanical and energetic parameters in competitive swimming. Among these studies, it is possible to identify the 400-m front crawl as a useful test to assess these parameters. The present study provided a meta-analysis assessing representative variables for the kinematic, arm-stroke efficiency, coordination, and energetic parameters of the 400-m front crawl test. PubMed, Embase, Web of Science, and SPORTDiscus were the databases used to select the studies published between January 1970 and December 2022. Forty studies (n = 651 swimmers) were selected according to the eligibility and inclusion criteria. The variables chosen to represent each parameter were: clean swim speed (kinematics); index of coordination (coordination); arm-stroke efficiency (efficiency); and oxygen consumption (energetic). Swimming speed was moderate (1.34 m s-1) compared to the world's records performers. Thus, this speed contributed for the swimmers in remaining at high efficiency (35%), imposing a capture coordination model (index of coordination: -11%) with high oxygen consumption (58.8 ml·kg-1 min-1). High heterogeneity (>75%) was found among the outcome parameters in the studies. The different average speeds that represented the kinematic parameters seem to be the most responsible and influential in the arm-stroke efficiency, coordination, and energetic parameters for high 400-m freestyle (front crawl) performance. This meta-analysis can help researchers, coaches, and swimmers improving competitive performance, and developing further research in the sports sciences area, specifically in the swimming.

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Acute psychological responses to physical activity may help explain long-term adherence to it. Thus, we compared acute psychological responses to different exercise protocols with identical durations. Eighteen moderately active young adults [Mage = 23, SD = 3 years; MVO2max (maximum oxygen consumption) = 42.8, SD = 4.3 mL·kg-1·min-1; MBMI (body mass index) = 24, SD = 2 kg·m-2] completed three low-volume exercise sessions in a crossover research design: (a) sprint interval training (SIT), (b) burpee interval training (BIT) requiring 10 × 5 second efforts with 35 seconds of passive recovery, and (c) a single bout of vigorous intensity continuous training (VICT) requiring 6 minutes and 5 seconds of running at ∼85% of peak heart rate (HRpeak). We assessed participants' ratings of perceived exertion (RPE), affective valence, enjoyment, intention, preference, and self-reported recovery and wellness before, during, and after each session. BIT was associated with significantly greater enjoyment, preference, and exercise intention (at 5 × week) than VICT (p ≤ .05). SIT elicited greater RPE (M = 5.38, SD = 2.00) than both BIT (M = 2.88, SD = 1.23) and VICT (M = 3.55, SD = 1.38) (p ≤ .05), and we observed a higher increase in RPE over time with SIT versus BIT (p = .019). For affective valence, SIT (M = 0.55, SD = 2.12) elicited a more aversive response than both BIT (M = 2.55, SD = 1.09) and VICT (M = 1.94, SD = 1.51) (p ≤ .05), and there was a higher increase in this aversive response to SIT over time (p < .05). Forty-eight-hour postexercise session muscle soreness was significantly lower with VICT than with BIT (p = .03). Overall, BIT was associated with more positive psychological responses than SIT and VICT.

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This study aimed (i) to verify if underwater horizontal, vertical and medio-lateral hand displacements (HD), in pull and push phases of the front crawl stroke, can be associated with arm-stroke efficiency (ƞp) and (ii) to compare np and selected kinematic variables between male and female swimmers. Ten male and 10 female swimmers performed an all-out front crawl 25-m test. Data were obtained with six synchronised video cameras (60 Hz) and analysed with a three-dimensional method. Results for males and females were respectively, as follows: (i) horizontal HD: 0.55 ± 0.06 m and 0.61 ± 0.09 m (p = 0.062; d = 0.78); vertical HD: 0.68 ± 0.06 m and 0.58 ± 0.07 m (p < 0.001; d = 1.53); and medio-lateral HD: 0.22 ± 0.07 m and 0.16 ± 0.03 m (p = 0.012; d = 1.11); (ii) ƞp: 0.33 ± 0.02 and 0.32 ± 0.03 (p = 0.48; d = 0.39); (iii) vCOM: 1.77 ± 0.06 m∙s-1 and 1.55 ± 0.10 m∙s-1 (p < 0.001; d = 2.42). Multiple linear regression (p = 0.019) indicated that horizontal and medio-lateral HD were able to predict np. The lower the horizontal hand displacement, the higher the ƞp.

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Understanding fluctuations and associations between swimming performance-related variables provide strategic insights into a swimmer's preparation program. Through network analysis, we verified the relationships between anthropometrics, maturation, and kinematics changes (Δ) in 25-m breaststroke (BREAST) and butterfly (FLY) swimming performance, before and after a 47-week swimming training season. Twenty age-group swimmers (n =11 girls: 10.0 ± 1.3 years and n = 9 boys: 10.5 ± 0.9 years) performed a 25-m all-out swim test (T25) in BREAST and FLY techniques, before and after 47 weeks. Three measures of centrality, transformed into a z-score, were generated: betweenness, closeness, and strength. Data were compared (t-test) and effect sizes were identified with Hedges' g. Large effect sizes were observed for swimming performance improvements in BREAST (32.0 ± 7.5 to 24.5 ± 3.8 s; g = 1.26; Δ = -21.9 %) and FLY (30.3 ± 7.0 to 21.8 ± 3.6 s; g = 1.52; Δ = -26.5 %). Small to moderate effect sizes were observed for anthropometric changes. Moderate effect size was observed for maturity offset changes (-2.0 ± 0.9 to -1.3 ± 1.0; g = 0.73; Δ = 50.9 ± 281 %). Changes in maturity offset, stroke rate (SR), and stroke length for both BREAST and FLY swimming speeds were highlighted by the weight matrix. For betweenness, closeness, and strength, changes in arm span (AS) (BREAST) and stroke length (FLY) were remarkable. The dynamic process of athletic development and the perception of complexity of fluctuations and associations between performance-related variables were underpinned, particularly for simultaneous swimming techniques in age-group swimmers.

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Abstract Aims: analyze kinematics, anthropometrics, and maturation during a training season in 12 y and underage-group swimmers, quantifying changes and estimating their contributions to the 200-m maximal front crawl time trial test (T200) (time trial/fixed distance), as an event representative of the swimming performance. Methods: Nineteen age-group swimmers (11 girls and 8 boys; age 10.0 ± 1.3 y and 10.6 ± 1.0 y) performed a T200 four times during the training season. Changes in kinematic and anthropometric variables throughout the season were calculated. We applied generalized estimating equations to compare the variables over the four experimental tests. Multiple linear regressions were applied to identify the most influential variables and the relative contribution of anthropometrics and kinematics to swimming performance of T200 at baseline (pre-season) and after (using delta values) each macrocycle. Results: Large improvements (d = 1.76) were observed in the T200's performance (from 85.5 ± 38.2 at pre-season to 175.2 ± 50.1 FINA points at the end season). A gender effect was not identified. Stroke rate, stroke length, and stroke index explained, respectively 59, 23, and 17% of the T200 performance changes along the season (R2 = 0.81; F = 26.9; p < 0.001; Durbin-Watson: 1.5). Anthropometric was not related to performance changes, with kinematic being the most determinant factor. Conclusion: Kinematical approaches must be carefully considered by coaches when planning 12 y and underage-group swimmers training programs.

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Abstract Background: Walking is an economic activity, the more efficient the mechanical contribution, the less metabolic energy is necessary to keep walking. Patients with chronic heart failure and heart transplant present peripheral musculoskeletal disorders, dyspnea, and fatigue in their activities. Objective: In this scenario, the present study sought to verify the correlations between metabolic and electromyographic variables in chronic heart failure, heart transplant patients, and healthy controls. Methods: Regression and correlation between cost of transport and electromyographic cost, as well as correlation between oxygen consumption and muscle coactivation in patients and controls at five different walking speeds have been performed, with alpha = 0.05. Results: Strong correlation values (r controls: 0.99; chronic heart failure: 0.92; heart transplant: 0.88) indicate a linear relationship between the cost of transport and electromyographic cost. Oxygen consumption was significantly correlated to muscle activation in all groups. Conclusion: These results suggested that dynamic muscle coactivation was an important factor, especially for CHF and HT. These data support the idea that peripheral muscle limitations play an important role in people with CHF and HT. These findings indicate a strong relation between metabolic and electromyographic variables. For chronic heart failure and heart transplant patients, it can help to explain some difficulties in daily activities and aid in physical rehabilitation.

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Este estudo tem por objetivo propor diretrizes teórico-práticas para a construção de metodologias de ensino do Polo Aquático (PAq). Pretende apontar conteúdos indispensáveis na iniciação ao PAq para crianças (6 a 10 anos de idade) e apresentar atividades práticas para o processo de ensino-aprendizagem através de uma revisão narrativa de materiais pertinentes ao tópico na forma de ensaio. Clareza de lingua-gem, pertinência prática e representatividade do item foram avaliados por três especialistas e o coeficiente de validade de conteúdo geral foi de 0,91. A proposição de atividades baseadas em referenciais teóricos pode guiar os profissionais de educação física a ampliar o leque pedagógico de maneira sólida (AU).

This study aims to propose theoretical and practical guidelines for the construction of a teaching methodologies for Water Polo (PAq). It intends to point out indispensable contents in the initiation to PAq for children (6 to 10 years old) and to present practical activities for the teaching-learning process through a narrative review of materials pertinent to the topic in the form of an essay. Clarity of language, practical relevance and representativeness of the item were assessed by three experts and the overall content validity coefficient was 0.91. The proposition of activities based on theoretical references can guide physical education professionals to expand the pedagogical range in a solid way (AU).

Este estudio tiene como objetivo proponer pautas teóricas y prácticas para la construcción de metodologías de enseñanza para Water Polo (PAq). Busca señalar contenidos indispensables en la iniciación a PAq para niños (6 a 10 años) y presentar actividades prácticas para el proceso de enseñanza-aprendizaje a través de una revisión narrativa de materiales pertinentes al tema en forma de ensayo. Tres expertos evaluaron la claridad del lenguaje, la relevancia práctica y la representatividad del ítem y el coeficiente de validez de contenido general fue 0,91. La propuesta de actividades basadas en marcos teóricos puede orientar a los profesionales de la educación física a ampliar enormemente el abanico pedagógico (AU).

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RESUMO

Este estudo tem por objetivo propor diretrizes teórico-práticas para a construção de metodologias de ensino do Polo Aquático (PAq). Pretende apontar conteúdos indispensáveis na iniciação ao PAq para crianças (6 a 10 anos de idade) e apresentar atividades práticas para o processo de ensino-aprendizagem através de uma revisão narrativa de materiais pertinentes ao tópico na forma de ensaio. Clareza de lingua-gem, pertinência prática e representatividade do item foram avaliados por três especialistas e o coeficiente de validade de conteúdo geral foi de 0,91. A proposição de atividades baseadas em referenciais teóricos pode guiar os profissionais de educação física a ampliar o leque pedagógico de maneira sólida.

This study aims to propose theoretical and practical guidelines for the construction of a teaching methodologies for Water Polo (PAq). It intends to point out indispensable contents in the initiation to PAq for children (6 to 10 years old) and to present practical activities for the teaching-learning process through a narrative review of materials pertinent to the topic in the form of an essay. Clarity of language, practical relevance and representativeness of the item were assessed by three experts and the overall content validity coefficient was 0.91. The proposition of activities based on theoretical references can guide physical education professionals to expand the pedagogical range in a solid way.

Este estudio tiene como objetivo proponer pautas teóricas y prácticas para la construcción de metodologías de enseñanza para Water Polo (PAq). Busca señalar contenidos indispensables en la iniciación a PAq para niños (6 a 10 años) y presentar actividades prácticas para el proceso de enseñanza-aprendizaje a través de una revisión narrativa de materiales pertinentes al tema en forma de ensayo. Tres expertos evaluaron la claridad del lenguaje, la relevancia práctica y la representatividad del ítem y el coeficiente de validez de contenido general fue 0,91. La propuesta de actividades basadas en marcos teóricos puede orientar a los profesionales de la educación física a ampliar enormemente el abanico pedagógico.

RESUMO

The aim of the study was to verify the relative contributions of energetic and kinematic parameters to the performance in 400-m front crawl test. Fourteen middle-distance swimmers participated in the study. Oxygen consumption was measured directly and blood samples were collected to assay lactate concentration. Both oxygen consumption and lactate concentration were used to calculate the: (i) overall energy expenditure, (ii) anaerobic (alactic and lactic) and (iii) aerobic contributions. The mean centre of mass speed and intracycle velocity variation were determined through three-dimensional kinematic analysis. Mean completion time was 315.64±26.91s. Energetic contributions were as follows: 6.1±0.28% from alactic anaerobic metabolism, 5.9±0.63% from anaerobic lactic and 87.8±0.88% from aerobic. Mean intracycle velocity variation was 0.14±0.03. The results indicated that performance of 400-m test relies predominantly on aerobic power. Parameters such as lactate, mean speed, anaerobic lactic and alactic (kW) correlated with performance of 400-m test (p <0.05). Multiple linear regressions indicated that mean centre of mass speed and anaerobic alactic (kW) determined the 400-m test performance (R2=0.92). Even though the T400 is characterized by aerobic metabolism, the anaerobic alactic component cannot be negligible at this competition level.

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