I am stacking NO2 and CE2, but I have also been taking GNC Triflex, GNC Mega Man Sports and Xenderine. My main desire is to be a runner but I also want to muscle up and get good tone. Are the other supplements going to be problem or will they in any way interfere with the NO2 and CE2?

When it comes to these two muscle "pumpers", there are generally no side effects to begin with. Depending on the individual, if you take no2, you may get diaria or migranes with some naseua. I suspect these side effects become more likely if you take the dosages in time intervals too close; you must let the body "take care" of one dosage before consuming the next. If you don't experience side effects from either no2 or ce2, chances are you will not see any side effects when taken with other sport suppliments. Every individual will react differently but generally, no studies have been taken to test side effects when taken with OTHER performance enhancers.

Anyway, if your true desire is to be a runner, all you should hope for is good definition. With all the calories runners burn, it would be near impossible to keep nice arm muscles simply because the body will see the arms as "useless" in aiding in long interval training. You never see marathon runners with big arms or chests. If you want big arms, skip the running. If you want DEFENITION, try doing higher reps and sets of 3 instead of low high intensity reps.

Good luck