TO the OP: The cardio thing needs to be broken down to me..
First off, I thought cardio is good for the heart? I do understand the theory of AAS+cardio=enlarged heart. However the theory behind that is that the heart races extremely fast? But does it not race extremely fast when we are pumping the iron getting in 2-3 extra reps at the end while our faces look like ripe tomatoes?
On top of that doesn't gear spike up cholesterol? Especially things like Tren(what I am on now) are notorious for spiking cholesterol. Bad cholesterol can be treated with a good diet yes, but you still need to do cardio to keep it under control. High cholesterol=unhappy heart.
Lastly, I think I read in one of the posts that by now cardio, you mean that no crazy HIIT training....so I am assuming walking the stair master or the treadmill for 30 min is fine? (serious question) Because when I do it, I always check my pulse since all the cardio machines now a days have that on them and my heart rate the whole time during cardio is in the 125-140 range(I do controlled breathing while on them)
HOWEVER your theory of heart racing too fast on gear can lead to an enlarged heart is interesting and scary. Like I said, for me cardio is not that bad but when I lift my heart is easily in the 170-200 range. I cannot "calmly" lift.