Influence of exercise mode and maximal lactate-steady-state concentration on the validity of OBLA to predict maximal lactate-steady-state in active individuals.

The aim of this study was to analyze the effects of exercise mode on the validity of onset of blood lactate accumulation (OBLA-3.5-mM fixed blood lactate concentration) to predict the work-rate at maximal lactate steady state (MLSS(work-rate)). Eleven recreationally active males (21.3+/-2.9 years, 72.8+/-6.7kg, 1.78+/-0.1m) performed randomly incremental tests to determine OBLA (stage duration of 3min), and 2 to 4 constants work-rate exercise tests to directly determine maximal lactate steady state parameters on a cycle-ergometer and treadmill. For both exercise modes, the OBLA was significantly correlated to MLSS(work-rate), (cycling: r=0.81 p=0.002; running: r=0.94, p<0.001). OBLA (156.2+/-41.3W) was lower than MLSS(work-rate) (179.6+/-26.4W) during cycling exercise (p=0.007). However, for running exercise, there was no difference between OBLA (3.2+/-0.6ms(-1)) and MLSS(work-rate) (3.1+/-0.4ms(-1)). The difference between OBLA and MLSS(work-rate) on the cycle-ergometer (r=0.86; p<0.001) and treadmill (r=0.64; p=0.048) was significantly related to the specific MLSS. We can conclude that the validity of OBLA on predicting MLSS(work-rate) is dependent on exercise mode and that its disagreement is related to individual variations in MLSS.