ABSTRACT
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.
ABSTRACT
O objetivo deste artigo foi efetuar uma revisão da origem do conceito e da aplicação da velocidade crítica (VC) na natação. Em relação ao significado fisiológico, aumentos substanciais de alguns marcadores fisiológicos (concentração de lactato, consumo de oxigênio e frequência cardíaca) foram observados durante esforços em intensidade retangular à VC, sugerindo que esta se situe acima do limiar anaeróbio e também da máxima fase estável de lactato. É sugerido que a VC seja influenciada por alguns fatores como: (1) utilização de diferentes combinações de distâncias para a sua determinação; (2) diferentes faixas etárias e (3) nível de experiência do nadador. Pode-se concluir que a VC é um adequado parâmetro para o controle dos efeitos do treinamento, e pode ser obtida de maneira simples em relação a outras formas de controle. No entanto, sua utilização como ferramenta para a predição do desempenho em natação ainda necessita ser melhor investigada.
The aim of this paper was to review the origin of the critical speed (CS) concept and how it may be applied to swimming. Regarding the physiological significance, substantial increases in some physiological markers (blood lactate, oxygen consumption and heart rate) were observed in rectangular intensity efforts during the CS, suggesting that this is above the anaerobic threshold and the maximal steady state lactate. Factors influencing CS are thought to include (1) using different combinations of distances used in the test to determine CS, (2) age of the individual, and (3) the swimmers level of experience. It can be concluded that the CS represents an adequate tool for controlling training intensity and has the benefit of being comparatively simple to measure in relation to others forms of control. However, use of CS as a tool for predicting performance in swimming still needs further investigation.