I have taken different NO2 prducts for awhile. Yeah that shit is amazing. But Im worried that when I stop taking it will my endurance suffer because I am no longer having my veins opened up wider and more oxygen intake coming in. Less oxygen and blood to a muscle as we all know means less output. Does this shit also hurt my bodies natural ability to use oxygen from air too? I ask this because im wondering what the effects will be of not taking it if IM running around moutains at 15,000ft or higher.