I don't like ez bar curls because you dont get a decent contraction, but it doesnt really matter.
With cardio I wouldnt worry about it unless youre trying to lose fat in which case keep off the treadmill - do high intensity things like sprint backs (eg go to a soccer field, sprint one way, jog back).
If you eat 4 square meals a day and get 1g of protein per pound of bodyweight you could probably gain 10-15 honest kilos on something like this, which is a lot. I would really stress not worrying about how you look until you get to 140/100/180 - THEN look in the mirror because there will be a difference.
goodluck mate.