Reverse lactate threshold test accurately predicts maximal lactate steady state and 5 km performance in running

Area of Science:

• Exercise Physiology
• Sports Science
• Biotechnology

Background:

• Accurate determination of physiological thresholds is crucial for optimizing endurance training and performance prediction.
• Existing methods like the onset of blood lactate accumulation (OBLA) have limitations in precision for maximal lactate steady state (MLSS) and race performance.
• The reverse lactate threshold (RLT) presents a novel approach to assess exercise intensity and performance metrics.

Purpose of the Study:

• To evaluate the accuracy of the reverse lactate threshold (RLT) test in determining running speed at maximal lactate steady state (MLSS).
• To assess the RLT test's ability to predict 5 km running performance.
• To compare the accuracy of RLT with the onset of blood lactate accumulation (OBLA) for these physiological markers.

Main Methods:

• Two studies were conducted: Study 1 (n=16) compared RLT and OBLA against MLSS determined by constant-speed tests.
• Study 2 (n=23) compared RLT against 5000 m all-out run performance.
• The RLT protocol involved a stepwise speed increase followed by a gradual decrease, with lactate equivalents analyzed during the reverse phase.

Main Results:

• RLT demonstrated excellent concordance with MLSS (ICC = 0.98), significantly higher than OBLA (ICC = 0.83).
• RLT showed a very high correlation with 5000 m running speed (r = 0.97).
• Mean differences for MLSS were minimal for RLT (+0.06 ± 0.05 m·s⁻¹) compared to OBLA (+0.13 ± 0.23 m·s⁻¹).

Conclusions:

• The reverse lactate threshold (RLT) test exhibits exceptional accuracy and agreement for predicting maximal lactate steady state (MLSS) and 5 km running performance.
• RLT may be a superior field test method for assessing running performance compared to traditional threshold concepts like OBLA.
• Further research is warranted to investigate the RLT test's sensitivity and utility within training programs.