Individuals with a low maximum fat oxidation capacity or high lactate production likely have poor mitochondrial function.

“And so similarly, maybe somebody walks around with a resting our Q of 0.8 and you think oh, they're perfectly fine But you see that their zone 2 level, the level at which they tap out at their fat oxidation maximum or their maximum aerobic output, is much lower than predicted. And now you have a functional assay. Exactly. You can categorize people by looking at the fat and also looking at the lactate. If you burn very little fat... that means that you don't have a good mitochondrial function and that confirms it, that test. If you produce a lot of lactate, that means that you don't have a good mitochondrial function either because lactate is metabolized in the mitochondria. So if it's in the blood, that means that the mitochondria cannot metabolize it.”