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What is AT?


Anaerobic or Lactate Threshold, commonly called AT, is where the body can't sustain metabolism in exercise with a combination of oxygen and fuel.

Because the demands of the activity are so high, the body shifts to progressively more anaerobic (without O2) sources of fuel, which are all carbohydrate-based. The burn you feel during exercise is this resulting lactic acid the body can't clear effectively. This level determines your ability to burn kcal in steady-state or endurance exercise.

Whether you want to lose weight or run faster, having a higher AT is the difference maker in that it sets the upper limit of your aerobic training zones. You can train your body to have a higher AT point by knowing where that AT point is currently, and then using interval training, like a spinning class, in conjunction with your personal heart rate training zones.

AT Graph

AT Graph

The average person off the street has an AT level at approximately 45% of their peak fitness speed, while Lance Armstrong's last recorded level was 93% of his peak speed. The higher your AT point, the faster you can go in actual speed or just burning more kcal.