Comparison of Modelled Maximal Lactate Steady State with Critical Power in Elite Cyclists

Area of Science:

• Exercise Physiology
• Sports Science
• Cycling Performance Analysis

Background:

• Maximal lactate steady state (MLSS) and critical power (CP) are key physiological markers for endurance performance.
• Accurate assessment of these markers is crucial for effective training prescription in professional cycling.

Purpose of the Study:

• To compare modelled MLSS with field-assessed CP in elite male professional cyclists.
• To explore relationships between maximal oxygen consumption (VO2max), maximal rate of blood lactate accumulation (MR.La), and maximal mean power outputs of varying durations.

Main Methods:

• Twelve highly trained professional cyclists completed six maximal tests.
• MLSS was modelled using VO2max, resting oxygen uptake, MR.La, and body mass.
• CP was estimated from 3-minute and 20-minute maximal mean power outputs.

Main Results:

• Modelled MLSS (357±30.6 W) and CP (364±21.5 W) showed a strong group-level correlation (r=0.881, p<0.001).
• VO2max correlated significantly with 3-min (r=0.646), 20-min (r=0.846), and CP (r=0.858).
• No significant correlation was found between MR.La and maximal mean power outputs.

Conclusions:

• Modelled MLSS can predict CP effectively on a group level in elite cyclists.
• Substantial individual variability exists between modelled MLSS and CP, questioning their conceptual equivalence.
• Practitioners should be aware of this individual variation when applying these concepts in cycling training.