The Role of l Carnitine in Mitochondria, Prevention of Metabolic Inflexibility and Disease Initiation Nature's Bounty L Carnitine Amino Acid Supplement, 500 mg30 caplets 1 Each Acetyl L Carnitine is more thought of as a fat burner. It's actually powerful tool for athletes looking to improve endurance, energy, and mental performance. Here's how you can integrate it into your routine for Acetyl L Carnitine 500 mg L Carnitine Protocol for Life Balance