Acetyl-L-carnitine is broken down in the blood by plasma esterase to carnitine which is used by the body to transport fatty acids into the mitochondria for breakdown.
So why use Acetyl-L-carnitine instead of normal old L-carnitine?
According to the manufactures this form of carnitine is absorbed by the body better than regular L-carnitine. Some studies show that Acetyl-L-carnitine is superior to L-carnitine in terms of bioavailability.
How does Acetyl-L-carnitine work in the carnitine shuttle system?
During strenuous exercise, a large portion of L-carnitine and unused acetyl-CoA are converted to Acetyl-L-carnitine and CoA inside mitochondria by the enzyme carnitine acetyltransferase.