Diet
Cardio
Side Laterals
NO2
none of that matters, whatsoever. and heavy overhead presses and even light front raises are what will get that vein popping like crazy while you are in the gym and some AAS is pumping in your blood, not fucking NO2 whatever that is.
but you don't even need to train much or eat anything special, and you certainly don't need cardio. as i said, if you have been in this game for long enough and you are on EQ, tren, GH and you understand the importance of Var, then you have veins fucking
everywhere and you are not over 7% unless you are on a run of slin.
i am on the above plus primo and even my calfs have a dozen or so huge veins. it's a good look at 230.