"He is near but not at the top aerobically, having a VO2 max of 83.8 mL/kg/min much higher than the average person (40-50) but not as high as that of some other elite cyclists, such as Miguel Indurain (88.0, although reports exist that Indurain tested at 92-94) or Greg LeMond (92.5).[2] His heart is 30% larger than average; however, an enlarged heart is a common trait for many other athletes. He has a resting heart rate of 32-34 beats per minute with a max heart rate at 201 bpm.[3] Armstrong's most unusual attribute may be his low lactate levels. During intense training, the levels of most racers range from 12 μL/kg to as much as 20 μL/kg; Armstrong is below 6 μL/kg. The result is that less lactic acid accumulates in Armstrong's system, therefore it is possible that he feels less fatigue from severe efforts, and this may contribute to his ability to sustain the same level of physical effort as other elite racers with less fatigue and faster recovery times"
