When is the best time to take l-arginine amino acid for the veins to show? *i workout very hard* and what is the recommended daily dosage? is it safe?

When you wish: Congratulations on taking up strength training. Arginine is safe, it may help you build some muscle by stimulating growth hormone, and may indeed accent your being vascular though keeping lean and high blood volume by doing a lot of cardio and watching fats and carbs in your food will help more. See whether you look more vascular shortly after taking arginine, and if so, take it before show times.