Maximal constant 45 min running velocity gives maximal lactate steady state

The aim of the present study was to improve and confirm a time trial (TT) based method for determining anaerobic threshold (AnT) requiring minimal equipment.

Eighteen participants underwent three to five all-out TTs for at the most 60 min. Velocity of the TTs was adapted in 0.1 or 0.2 m*s-1 steps until maximal velocity maintainable for at least 45 min (V(max45)) was identified. Exercise was interrupted every 5 min in order to take blood samples. After the participants had finished their last TT blood lactate concentration (BLC) was determined to identify maximal lactate steady state (MLSS).

Velocity, BLC and heart rate (HR) at the TTs giving MLSS (TTMLSS) and giving V(max45) (TTV(max45)) were almost identical (3.45 ± 0.31 m*s-1 vs. 3.44 ± 0.31 m*s-1, 4.46 ± 1.28 mmol*L-1 vs. 4.52 ± 1.28 mmol*L-1, 177 ± 9.8 bpm vs. 178 ± 9.4 bpm). Coefficient of correlation (R) and standard error of estimate (SEE) between velocity at MLSS (VMLSS) and V(max45) were 0.96 and 0.09 m*s-1, respectively, indicating a very close relationship. Agreement between VMLSS and V(max45) was also very high. At VMLSS cardiovascular drift (CVD) was 8.4 ± 2.6 bpm from the 10th to 30th min. At V(max45) CVD was 7.9±2.8 bpm from the 10th to 30th min and 11.2 ± 3.8 bpm from the 10th to 45th min.

Determination of V(max45) is a manageable, cost-saving and precise method for predicting velocity and CVD at MLSS in healthy, ambitious and at least moderately trained runners.