I have tried the precision engineered line of NOS. Nitric Oxide is a high concentration of the amino acid L-Arginine. Dosages vary depending on the company, but most companies use 3000mg per serving (1000mg per tablet). At these high concentrations, L-Arginine has a vaso-dialating effect, therefore; enlarging the circumference of your blood vessels and supplying the area you are working with more blood. This is why you get a stronger pump throughout your workouts. Also, more blood equals more oxygen and nutrients delivered to your muscles, thus enhancing the growth process.
Although is supplement seems quite effective, unfortunately NOS has a negative affect on your immune system. Some individuals (including myself) experience strep throat quite often throughout the duration they are on it. To counter this, it is very important to have some Lysine on hand. For every 3000mg of L-Arginine (NOS) that you take, make sure you take 500mg of Lysine and all should be fine.
From my experiences with NOS, it definately gives you a noticible pump (especially on bi-cep curls), however; as far as it's size building capabilities go...it is nothing dramatic. I know all the advertisements say that you will stay pumped 24/7, and look as pumped as you do throughout your workouts, but this is simply not true. Everyones diff tho bro so go ahead and give it a go...can't hurt
