OCD Nutrition Level X contains a powerful synergistic blend of nitric oxide enhancers, including agmatine and citrulline. These two amino acids have particularly promounced effects when it comes to maximising blood flow and nutrient delivery to muscle tissue. Firstly, citrulline is an exceptional elevator of blood arginine levels, perhaps better than arginine itself! Arginine is the direct precursor to nitric oxide, acted upon by nitric oxide synthase. Additionally, agmatine is an inducer of nitric oxide synthase activity. So, here we have a precursor and a stimulator of nitric oxide synthesis, perfect companions for promoting this remarkable gas within the blood vessels. Alone, citrulline has been shown to reduce subjective feelings of muscular fatigue after exercise.