Evaluation of critical swimming velocity in young amateur swimmers

Abstract

The purpose of this study was to compare in amateur swimmers the critical swimming velocity (CV) with the swimming velocity corresponding to a blood lactate concentration of 4 mmol l−1 (V4). Ten amateur swimmers volunteered for this study (six men, age 22.3 ± 2 years; four women, age 21.3 ± 1 years) and performed a 7 × 200-m swimming test (at 70%, 75%, 80%, 85%, 90%, 95% and 100% of their 200-m best time) with 5 min rest between each repetition. Blood lactate concentration was determined after each repetition. V4 was determined from the speed-lactate curve. In order to calculate CV, the best front-crawl swimming results over 50, 100, 200 and 400 m were used. CV was expressed as the slope of the linear relationship between time and distance. Swimming velocities obtained with the two tests (CV 1.086 ± 0.151 m s−1; V4 1.087 ± 0.128 m s−1) were positively and significantly correlated (r = 0.93, p < 0.05) and no significant differences were found. A Bland-Altman plot showed a good agreement between the two measurement methods. These results confirm that the CV seems to be a valid and noninvasive method for also determining training intensities and monitor endurance capacity in less-experienced athletes.