Noninvasive estimation of the maximal lactate steady state in trained cyclists

Purpose: The purposes of this study were to estimate noninvasively the maxi mal lactate steady state (MLSS) in trained cyclists on a windload simulator with a velocity based technique and to determine whether the HR at MLSS (H RMLSS) elicited a similar blood lactate concentration (BLC) during field te sting. Methods: To determine and verify MLSS, 10 male cyclists performed fi ve to seven laboratory trials on separate days, including a (V) over dot O- 2max test; a 5-km time trial (TT); and two or more 30-min trials at specifi c percentages of each subject's average 5-km TT speed (AVS(5km)). Mean +/- SD for the following variables were obtained at MLSS: velocity was 90.3 +/- 2.7% of the AVS(5km), BLC was 5.4 +/- 1.6 mM, RPE was 15 +/- 2.1, (V) over dot O-2 was 80 +/- 6.3% of (V) over dot O-2max, and HR was 167 +/- 9.5 bea ts.min(-1), which was 88 +/- 3.8% of the mean maximum HR. Field tests inclu ded three laps of an 8-km road circuit at HRMLSS +/- 3 beats.min(-1) and on e lap at maximum sustainable velocity (a road TT). Results: There were no s ignificant differences in BLC, HR, and RPE between the three steady-state r oad laps and the lab MLSS trial. There was also good agreement between the road and lab MLSS velocity/TT velocity ratios. Conclusions: Our data sugges t that 5-km TT cycling velocity, as measured on a windload simulator, may b e used to estimate MLSS and the IIR at MLSS for training purposes.