Individual anaerobic threshold and maximum lactate steady state

Area of Science:

• Sports Science
• Exercise Physiology
• Biochemistry

Background:

• The individual anaerobic threshold (IAT) is determined by blood lactate levels during incremental exercise and recovery.
• Monitoring endurance training requires valid measures of exercise intensity and physiological response.

Purpose of the Study:

• To validate the IAT as a measure for maximum lactate steady state (max Lass).
• To assess the IAT's utility in monitoring endurance training.

Main Methods:

• Sixteen and 14 endurance-trained athletes performed incremental exercise tests on a cycle ergometer and treadmill, respectively, to determine IAT and 4 mmol/L lactate threshold (AT).
• Subsequent endurance tests were conducted at varying percentages of IAT (85-105%) and 100% of AT to assess lactate stability and endurance capacity.
• Blood lactate concentrations and exercise performance were monitored throughout the tests.

Main Results:

• Lactate steady state (Lass) was maintained at 85%, 95%, and 100% of IAT intensities.
• At 105% of IAT and 100% of AT intensities, continuous lactate increase or premature exhaustion occurred.
• Athletes with an AT below their IAT achieved Lass at 100% AT intensity.

Conclusions:

• The IAT is a valid indicator of the maximum lactate steady state (max Lass).
• IAT-derived intensities are effective for endurance training, with 100% IAT representing the upper limit for sustained effort.
• The IAT provides a reliable benchmark for prescribing and monitoring endurance training intensity.