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Age-related performance determinants of young swimmers in 100- and 400-m events.

BACKGROUND
Swimming performance is influenced by several parameters, such as body composition, anthropometric and physiological parameters. However, the level of relative contributions of these variables to swimming performance in different age groups is unclear. Characteristics of body composition, anthropometry and neuromuscular variables were evaluated to identify determinant variables on 100- and 400-meter freestyle swimming events.


METHODS
Sixty swimmers from both sexes participated in the study. They were divided into three groups: 11, 12 years old (G1), 13, 14 years old (G2) and 15 to 23 years old (G3). Pearson's correlation and Stepwise multiple regression models were fitted to determine the relationships between performance and the parameters evaluated.


RESULTS
Results show that age plays a major role for G1 [(Time (100-m) = 236.737 - 13.323 (Age), r2= 0.51 and Time (400-m) = 831.070 - 39.014 (Age), r2=0.35]. Lean body mass, muscular power and anthropometric parameters were determinants of performance on G2 [(Time (100-m) = 81.964 - 0.504 (Lean) - 0.566 (CMJ Power) - 0.493 (Trunk width), r2= 0.83 and Time (400-m) = 592.536 - 3.471 (CMJ Power) - 1.679 (Length lower limbs), r2=0.57]. Muscular strength and body mass were determinants of performance for G3 [(Time (100-m) = 80.273 - 0.201 (PT Knee Flex 60°/s), r2=0.56 and Time (400-m) = 219.632 - 2.608 (Handgrip strength) + 2.917 (Body mass), r2=0.70].


CONCLUSIONS
These results contribute to the development of proper training programs for each age group (strength and power training are important to improve performance only after 13 years old) and to determine parameters of sports selection (antropometric variables are important for 100 and 400m swimming performance).