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400 meters freestyle pacing strategy and race pace training in age-group swimmers.

PURPOSE
This study aimed to characterize the 400 m freestyle pacing strategy, the effect of post-race feedback, and individualised race-pace training.


METHODS
Twenty male swimmers (13.4 ± 1.0 years) were randomly assigned into two groups. The experimental group used training monitoring based on intensities around 400 m pace (92 and 97% of 400 m speed), while, for the control group different heart rate zones (EN2 and EN2+) were used as an intensity criterion. The training volume was the same for both groups. A maximal 400 m freestyle simulated competition was performed before and after the 3 weeks period to determine intensities and to assess changes in performance. The rate of perceived exertion and heart rate values were also evaluated.


RESULTS
A fast start in the first 50-100 m, then a constant speed in the middle of the race and an end-spurt during the last 50-100 m was the pacing pattern adopted by the majority of the swimmers. Significant main effects of time were observed for 400 m time ( p = 0.001; ES 3.39; very large). Results revealed significant pre-to-post improvements from 328 ± 26.3 s to 317 ± 19.4 s in the experimental group and from 329 ± 25.2 s to 321 ± 21.1 s in the control group.


CONCLUSIONS
All the swimmers adopted almost the same parabolic pacing strategy before and after the training program with some differences in seconds that have made the strategy of the experimental group better balanced during the post-training test. Both training methods induced significant improvements in 400 m performance, to a greater extent for the training using intensities near 400 m race pace.