The aim was to characterize the oxygen uptake (VO2) kinetics during 100 and 400 m maximal swims. Materials and methods: Nineteen competitive swimmers aged 16-23 years (12 males, 7 females), categorized into sprinters (SP, n=10) and non-sprinters (non- NS, n=9), swum 100 and 400 m at maximal speed using the front crawl in a 50-m indoor pool. VO2 was measured breath-by-breath using a previously validated snorkel connected to a portable gas analyser (K4 b2, Cosmed, Italy). Data were subsequently averaged and fi tted to mono-exponential functions. Results: See Table 1. VO2 kinetics was fastest during the shortest swim, with time constants ô of 25.0 (SD 7.44) and 29.2 (4.78), respectively. ô was not different in SP as compared with non-SP in either distance (p > 0.05), and did not correlate with swimming speed (r = 0.01, 0.11). Peak VO2 signifi cantly correlated with speed both in 100 (r = 0.84) and 400 m (r = 0.78). Conclusions: As in other types of exercise, VO2 kinetics depends on swimming intensity and duration. ô for 100 m (23 s) is almost equal to that measured at the muscle level by NMRS (24 s). Fast O2 kinetics appears to be a general adaptation to training, possibly due to the prevalent type of interval training used in this sport.
© Copyright 2008 Archivos de medicina del deporte. Federación Española de Medicina del Deporte. All rights reserved.