L-carnitine helps the body produce energy. It is important for heart and brain function, muscle movement, and many other body processes. Carnitine plays a critical role in energy production. It transports long-chain fatty acids into the mitochondria so they can be oxidized ("burned") to produce energy. It also transports the toxic compounds generated out of this cellular organelle to prevent their accumulation. Because L-carnitine can be absorbed quickly into the body, especially when it's consumed in liquid form, the best time to take is in the morning and/or prior to workouts. It is recommended that you take between 2-4g of L-carnitine per day, divided into two or three evenly split dosages.