L carnitine is involved in transporting fatty acids into your cells' mitochondria to be burned for energy. During a bulk, the idea is to gain muscle, ideally with minirmal fat gain. Here's how, L Carnitine for Cutting vs Bulking: How It Works in Both Phases Nutrex Research L Carnitine 3000 Premium L Carnitine, Stimulant Free Workout Drink, 31 Servings, Lunar Pop Walmart.com When to Take L Carnitine for Optimal Training Benefits Transparent Labs