L arginine L citrulline 1000mg L arginine concentration: 750mg L citrulline concentration: 250mg Number of tablets: 60 tablets Arginine and citrulline are effective supporters of protein metabolism in the body, as they contribute to enhancing the protein synthesis process, and are essential nutrients that play a vital role in building and maintaining muscle tissue and cells. Therefore, arginine and citrulline help support muscle growth and enhance physical performance.