Most of your Glutamine and Carnitine are taken through consumption of meat, so if your diet is relatively low in meat, or you are vegan/vegetarian, than supplementing may be beneficial if you perform an exercise program of moderate to high intensity
This is often the first and only sign of gradual degradation that isn't visually apparent
How Bodybuilding Health+ Is Structured: Platform, Providers, and Pharmacies Bodybuilding Health+ materials describe a three-part operating structure
Weghuber D, Forslund A, Ahlstrom H, Alderborn A, Bergstrom K, Brunner S, et al
Boecking B, Rose M, Brueggemann P, Mazurek B