Ben Greenfield's Supplement Stack: Biohacking Tools for Energy, Detox & Longevity For Youth Boundless Health, Fitness and Energy: Ben Greenfield Explains How 24Life There's a lot of confusion around peptides and muscle. Here's how I actually think about it. Most peptides don't build muscle directly. They improve the systems that allow muscle to grow. First, L Carnitine: An Amino Acid Supplement for Athletes Ultimate Nutrition Ben Greenfield Authors Macmillan L Carnitine Liquid Force Factor