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- Establishing the changes in elite swimmers’ energetic and biomechanical profile during a winter seasonPublication . Costa, M.J.; Bragada, José A.; Mejias, J. Erik; Marinho, D.A.; Silva, A.J.; Louro, Hugo; Barbosa, Tiago M.Researchers are constantly trying to identify the factors that can predict with higher accuracy the swimming performance. This massive research has given special emphasis to the energetic and biomechanical assessments as the major determinants to enhance swimming performance (e.g. Barbosa et al., 2008).
- Stability and prediction of 100-m breaststroke performance during elite swimmers careerPublication . Costa, M.J.; Marinho, D.A.; Reis, Victor M.; Silva, A.J.; Bragada, José A.; Barbosa, Tiago M.Longitudinal performance assessment is important to help coaches defining realistic goals and training methods. The purpose of this study was to analyze the 100-m Breaststroke performance stability throughout the elite swimmer’s career, from children to adult age
- Longitudinal interventions in elite swimming: a systematic review based on energetics, biomechanics and performancePublication . Costa, M.J.; Bragada, José A.; Marinho, D.A.; Silva, A.J.; Barbosa, Tiago M.Longitudinal information requires the notion of repeated measurements throughout time. Such data is important because it allows the determination of the effectiveness of an intervention program. Research in competitive swimming has given special emphasis to energetics and biomechanics as determinant domains to improve performance. The purpose of this systematic review was to summarize longitudinal evidences on the energetic, biomechanical, and performance status of elite swimmers. A computerized search was made in 6 databases, conference proceedings, and department files. The 28 studies that satisfied the inclusion criteria were selected for analysis. Studies' qualitative evaluation was made by 2 independent reviewers using the Quality Index. These studies were then gathered into 3 main categories according to their reported data: energetics (n = 18), biomechanics (n = 9), and performance (n = 8). The conclusions were as follows: (a) elite swimmers are able to demonstrate from slight to substantial changes in their performance and energetic and biomechanical profiles within and between seasons; (b) the magnitude of change is dependent on the characteristics of the training programs, the duration of the intervention, and subject's gender; and (c) future research should emphasize the use of more complex procedures to improve the quality of the interventions.
- Stability and prediction of 100-m breaststroke performance during the careers of elite swimmersPublication . Costa, M.J.; Marinho, D.A.; Reis, Victor M.; Silva, A.J.; Bragada, José A.; Barbosa, Tiago M.The aim of this study was to track and analyze the 100-m Breaststroke performance stability throughout elite swimmer’s career. 35 Portuguese male top-50 were analyzed for seven consecutive seasons between 12 and 18 years old. Best performances were collected from ranking tables. Longitudinal assessment was performed based on two approaches: (i) mean stability was analyzed by descriptive statistics and ANOVA repeated measures for each season followed by a post-hoc test (Bonferroni test), (ii) normative stability was analyzed with self-correlation (Malina, 2001) and the Cohen’s Kappa tracking index (Landis and Koch, 1977). There was a 100-m Breaststroke performance enhancement from children to adult age. The overall career performance prediction was low. The change from 13 to 14 years can be a milestone, where the ability to predict the final swimmer’s performance level strongly increases.
- Monitoring the elite swimmer’s performance and energetical profile throughout a training seasonPublication . Costa, M.J.; Bragada, José A.; Mejias, J. Erik; Marinho, D.A.; Louro, Hugo; Silva, A.J.; Barbosa, Tiago M.
- Stability of elite freestyle performance from childhood to adulthoodPublication . Costa, M.J.; Marinho, D.A.; Bragada, José A.; Silva, A.J.; Barbosa, Tiago M.Stability of athletic performance is important for practitioners and coaches, since it allows the selection of appropriate training methods and prediction of ages for best results. We performed a longitudinal study of 1694 season-best performances of 242 elite-standard swimmers throughout their careers, from 12 to 18 years of age. Mean stability (descriptive statistics and oneway repeated-measures ANOVA, followed by a Bonferroni post-hoc test) and normative stability (Cohen’s kappa tracking index and the Pearson correlation coefficient) were determined for seven consecutive seasons. Performance improvements in all events were observed (14.36–18.97%). Bonferroni post-hoc tests verified changes in almost all events assessed. Cohen’s kappa demonstrated low stability (0.17–0.27) in relative performance. Pearson correlations only became high from 15 to 16 years in the 50-m and 100-m events, and from 16 to 17 years in the 200-m, 400-m, and 1500-m events. Our results show that: (a) swimmers should display a substantial improvement (14–19%) to become elite standard as adults, such as at 18 years; (b) 16 is the age at which the ability to predict adult performance increases markedly.
- Preditores antropométricos, bioenergéticos e biomecânicos dos 200 m crol num momento determinante da época de invernoPublication . Costa, M.J.; Bragada, José A.; Mejias, J. Erik; Marinho, D.A.; Louro, Hugo; Silva, A.J.; Barbosa, Tiago M.A performance em natação parece ser determinada pela relação hierárquica estabelecida entre um conjunto de factores (Barbosa et al., 2010). Esta está fortemente associada aos pressupostos bioenergéticos, enquanto estes são dependentes do comportamento biomecânico e das estratégias motoras adoptadas pelo nadador (Barbosa et al., 2010). No entanto, importa determinar criteriosamente quais as variáveis que mais e melhor predizem a variação da performance dentro de cada domínio (antropométrico, bioenergético e biomecânico).
- Tracking the performance, energetics and biomechanics of international versus national level swimmers during a competitive seasonPublication . Costa, M.J.; Bragada, José A.; Mejias, J. Erik; Louro, Hugo; Marinho, D.A.; Silva, A.J.; Barbosa, Tiago M.The purpose of this study was to track and compare the changes of performance, energetic and biomechanical profiles of international (Int) and national (Nat) level swimmers during a season. Ten Portuguese male swimmers (four Int and six Nat level subjects) were evaluated on three different time periods (TP1, TP2, TP3) of the 2009–2010 season. Swimming performance was assessed based on official time’s lists of the 200-m freestyle event. An incremental set of 7 9 200 m swims was applied to assess the energetic and biomechanical data. Measurements were made of: (1) velocity at the 4 mmol of lactate levels (V4), stroke index at V4 (SI@V4) and propelling efficiency at V4 (gp@V4), as energetic estimators; (2) stroke length at V4 (SL@V4) and stroke frequency at V4 (SF@V4), as biomechanical variables. The results demonstrated no significant variations in all variables throughout the season. The inter-group comparison pointed out higher values for Int swimmers, with statistical differences for the 200 m performance in all time periods. Near values of the statistical significance were demonstrated for the SI@V4 in TP1 and TP3. The tracking based on K values was high only for the SI@V4. It is concluded that a high stability can be observed for elite swimmers performance, energetic and biomechanical profiles throughout a single season. Int swimmers are able to maintain a higher energetic and biomechanical capacity than Nat ones at all times. The SI@V4 may be used as an indicator of performance variation.
- Modificações no perfil bioenergético e biomecânico de nadadores entre dois períodos "pré-taper"Publication . Costa, M.J.; Bragada, José A.; Mejias, J. Erik; Marinho, D.A.; Louro, Hugo; Silva, A.J.; Barbosa, Tiago M.O presente estudo procurou analisar as alterações ao nível do perfil bioenergético e biomecânico de nadadores de elite entre dois períodos “pré-taper”. Foram analisados 7 nadadores portugueses masculinos de elevado nível competitivo. Os parâmetros bioenergéticos e biomecânicos foram obtidos em dois momentos “pré-taper” (T1 e T2) antecedentes a competições importantes (Novembro e Março da época desportiva de 2009-2010). Foram analisadas as seguintes variáveis: (i) velocidade do equilíbrio máximo de lactato estimada às 4 mmol (V4), como indicador bioenergético; (ii) distância de ciclo à V4 (DC@V4), frequência gestual à V4 (FG@V4), índice de nado à V4 (IN@V4) e eficiência propulsiva à V4 (ηp@V4), como indicadores biomecânicos. A comparação entre os dois momentos de avaliação foi efectuada com recurso à estatística não paramétrica Teste de Wilcoxon. Verificámos aumentos com significado estatístico na V4 e na FG@V4 de T1 para T2. A DC@V4, o IN@V4 e a ηp@V4 apresentaram-se estáveis, sem variações significativas. Do ponto de vista da análise individual, 4 dos 7 nadadores aumentaram o seu IN@V4. Em síntese, existe uma tendência para o aumento da V4 ao longo da época desportiva. As alterações na V4 em nadadores de elite parecem ser decorrentes de modificações nos parâmetros biomecânicos, mais precisamente no aumento da FG@V4.
- Net heart rate as estimating mean of the energy expenditure in walking/running and stationary bikePublication . Bragada, José A.; Bartolomeu, Raúl Filipe; São Pedro, Eric Macias deNet heart rate (HRnet) is known as the variation of the heart rate (HR) above the resting value, as a result of physical activity (PA). The positive association between HRnet, the level of PA and respective energy expenditure (EE) has been previously reported (Bragada et al., 2009; São Pedro et al., 2015). However, a useful and practical way of objectively calculates EE from HRnet is still needed. Thus, the aim of this study was to find an EE calculation formula based on HRnet measurement, in walking/running and stationary bike