Resumen de Ventilatory and Physiological Responses in Swimmers Below and Above Their Maximal Lactate Steady State
Mario C. Espada, Joana F. Reis, Tiago F. Almeida, Paula Marta Bruno, Verónica E. Vleck, Francisco B. Alves
The purpose of this study was to understand the ventilatory and physiological responses immediately below and above the maximal lactate steady-state (MLSS) velocity and to determine the relationship of oxygen uptake (V[Combining Dot Above]O2) kinetics parameters with performance, in swimmers. Competitive athletes (N = 12) completed in random order and on different days a 400-m all-out test, an incremental step test comprising 5 × 250- and 1 × 200-m stages and 30 minutes at a constant swimming velocity (SV) at 87.5, 90, and 92.5% of the maximal aerobic velocity for MLSS velocity (MLSSv) determination. Two square-wave transitions of 500 m, 2.5% above and below the MLSSv were completed to determine V[Combining Dot Above]O2 on-kinetics. End-exercise V[Combining Dot Above]O2 at 97.5 and 102.5% of MLSSv represented, respectively, 81 and 97% of V[Combining Dot Above]O2max; the latter was not significantly different from maximal V[Combining Dot Above]O2 (V[Combining Dot Above]O2max). The V[Combining Dot Above]O2 at MLSSv (49.3 ± 9.2 ml·kg-1·min-1) was not significantly different from the second ventilatory threshold (VT2) (51.3 ± 7.6 ml·kg-1·min-1). The velocity associated with MLSS seems to be accurately estimated by the SV at VT2 (vVT2), and vV[Combining Dot Above]O2max also seems to be estimated with accuracy from the central 300-m mean velocity of a 400-m trial, indicators that represent a helpful tool for coaches. The 400-m swimming performance (T400) was correlated with the time constant of the primary phase V[Combining Dot Above]O2 kinetics ([tau]p) at 97.5% MLSSv, and T800 was correlated with [tau]p in both 97.5 and 102.5% of MLSSv. The assessment of the V[Combining Dot Above]O2 kinetics in swimming can help coaches to build training sets according to a swimmer�s individual physiological response.
