Purpose: The purpose of this study was to investigate the validity of the lactate minimum test ([Lac-]BMIN) in the determination of the velocity at the maximal lactate steady state (V-MLSS), and to identify those physiological factors most closely associated with 8-km running performance.
Methods: Thirteen trained male runners (VO2max range 53-67 mL.kg-1.min-1) took part in an 8-km simulated race on flat roads and completed a comprehensive battery of laboratory tests.
Results: Performance velocity was most strongly correlated with the estimated running velocity at VO2max (r = 0.93) and with V-MLSS (r = 0.92) and velocity at lactate threshold (V-Tlac) (r= 0.93). The running velocity at the ventilatory threshold (V-Tvent) (r = 0.81) and the [Lac-]BMIN (r = 0.83) also produced good correlations with performance velocity. Performance running velocity (mean +/- SEM 16.0 +/- 0.3 km.h-1) was not significantly different from V-MLSS (15.7 +/- 0.3 km.h-1). The running velocity at [Lac-]BMIN (14.9 +/- 0.2 km.h-1) was not significantly different from the V-Tlac (15.1 +/- 0.3 km.h-1) or V-Tvent (14.9 +/- 0.2 km.h-1) was not significantly different from the V-Tlac (15.1 +/- 0.3 km.h-1) or V-Tvent (14.9 +/- 0.3 km.h-1) but was significantly lower than the V-MLSS (P < 0.05). The [Lac-]BMIN provided the lowest correlation with V-MLSS (r = 0.61) and the worst estimate of V-MLSS (SEE = 0.75 km.h-1) compared with the other measures of lactate accumulation. The V-Tlac was not significantly different from V-MLSS and provided the highest correlation (r = 0.94) and a close estimate (SEE = 0.33 km.h-1) of the V-MLSS.
Conclusions: It is concluded that of the measures studied relating to blood lactate accumulation during submaximal exercise, V-Tlac provides the best estimate of the V-MLSS and the V-Tlac had equal predictive power for 8-km race performance.