My Nutriplus L Carnitine Shot Experience: Energy Boost & Fat Burn! L Carnitine is Underrated. New Meta Review Reminds Us Why. Early research into L carnitine was often cited as underwhelming, showing negligible changes in muscle carnitine content and fat loss outcomes. However, these findings may have been limited by a short study window Accelerate Your Weight Loss Journey With Nutrex Research L Carnitine 3000 Helps Convert Stored Body Fat Into Usable Energy Enhances Physical Endurance & Cardiovascular Performance Maximum Strength