what is carnitine used for
L-carnitine is used for conditions of the heart and blood vessels including heart-related chest pain, congestive heart failure (CHF), heart complications of a disease called diphtheria, heart attack, leg pain caused by circulation problems (intermittent claudication), and high cholesterol. Intense exercise has been linked to a decrease in L-carnitine blood levels. 2  However, research on the use of L-carnitine for improving athletic performance is inconsistent. 3  Some studies suggest that L-carnitine improves athletic performance and endurance.