Validity of a single-visit protocol to estimate the maximum lactate steady state

Area of Science:

• Exercise Physiology
• Sports Science
• Biophysics

Background:

• The maximum lactate steady state (MLSS) is crucial for endurance performance, representing the highest exercise intensity with balanced lactate production and clearance.
• Traditional MLSS determination requires multiple lab visits, making it time-consuming and labor-intensive.

Purpose of the Study:

• To evaluate the accuracy of a novel single-visit protocol for estimating MLSS compared to the traditional multi-visit method.
• To determine if a simplified MLSS measurement can reliably replace the established protocol.

Main Methods:

• Eight endurance-trained runners underwent an incremental VO2peak test.
• MLSS was measured using both a traditional 4-5 visit protocol (MLSStrad) and a single-visit protocol (MLSSsingle) involving two constant-speed runs.
• Blood lactate, oxygen uptake, and heart rate were monitored throughout.

Main Results:

• The single-visit MLSS (MLSSsingle) significantly underestimated MLSStrad in terms of speed, heart rate, blood lactate levels, and %VO2peak.
• MLSSsingle speed and MLSStrad speed showed a poor correlation (r=0.29).

Conclusions:

• The single-visit protocol substantially underestimates the actual maximum lactate steady state.
• This simplified method is not recommended as a replacement for the traditional MLSS determination in endurance athletes.