Supplement of the week: L Carnitine! This one doesn't just boost fat metabolismit can also improve recovery, endurance, and even brain function. If you're serious about performance and longevity, this might be L Carnitine: Benefits, Side Effects, And Dosage, Per Dietitians How Long Should You Take L Carnitine for Weight Loss Results? Should I use L Carnitine on rest days or just before workouts? Amazon.com: Liquid L Carnitine 3000 Plus Advanced 4 in 1 Formula with Acetyl L Carnitine, L Tartrate, ProGBB & Vitamin B, Stimulant Free High Absorption L Carnitine Supplement for Energy & Metabolism, 16oz : Health & Household