The Lactate Minimum Test protocol provides valid measures of cycle ergometer V̇O2peak

Abstract

Aim. The aim of the present study was to investigate the validity of the Lactate Minimum Test (LMT) for the determination of peakV̇O2 on a cycle ergometer and to determine the submaximal oxygen uptake (V̇O 2) and pulmonary ventilation (VE) responses in an incremental exercise test when it is preceded by high intensity exercise (i. e., during a LMT). Methods. Ten trained male athletes (triathletes and cyclists) performed 2 exercise tests in random order on an electromagnetic cycle ergometer: 1) Control Test (CT): an incremental test with an initial work rate of 100 W, and with 25 W increments at 3-min intervals, until voluntary exhaustion; 2) LMT: an incremental test identical to the CT, except that it was preceded by 2 supramaximal bouts of 30-sec (∼120% V̇O2Peak) with a 30-sec rest to induce lactic acidosis. This test started 8 min after the induction of acidosis. Results. There was no significant difference in peak V̇O 2 (65.6±7.4 ml.kg-1.min-l; 63.8 ± 7.5 ml.kg-1.min-1 to CT and LMT, respectively). However, the maximal power output (POmax) reached was significantly higher in CT (300.6±15.7 W) than in the LMT (283.2±16.0 W). V̇O 2 and VE were significantly increased at initial power outputs in LMT. Conclusion. Although the LMT alters the submaximal physiological responses during the incremental phase (greater initial metabolic cost), this protocol is valid to evaluate peakV̇O2, although, the POmax reached is also reduced.