VENTILATORY AND PHYSIOLOGICAL RESPONSES IN SWIMMERS BELOW AND ABOVE THEIR MAXIMAL LACTATE STEADY STATE

Espada, MC, Reis, JF, Almeida, TF, Bruno, PM, Vleck, VE, and Alves, FB. Ventilatory and physiological responses in swimmers below and above their maximal lactate steady state. J Strength Cond Res 29( 10): 2836- 2843, 2015- 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 ( VO2) 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 3 250and 1 3 x200- 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 VO2 O2 on-kinetics. End-exercise VO O2 at 97.5 and 102.5% of MLSSv represented, respectively, 81 and 97% of VO2 max; the latter was not significantly different from maximal V O2 ( V O2max). The V O2 at MLSSv ( 49.3 +/- 6 9.2 ml center dot kg21 center dot min-1) was not significantly different from the second ventilatory threshold ( VT2) ( 51.3 +/- 6 7.6 ml center dot kg-1 center dot min21). The velocity associated with MLSS seems to be accurately estimated by the SV at VT2 ( vVT2), and vV 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 O2 kinetics ( tp) at 97.5% MLSSv, and T800 was correlated with tp in both 97.5 and 102.5% of MLSSv. The assessment of the V O2 kinetics in swimming can help coaches to build training sets according to a swimmer's individual physiological response.