When bulking should I be cutting out all cardio and just lifting, or combine the 2?
cardio is good for heart health but isn't essential (even for cutting)
if you plan to do cardio, you have to account for the extra calorie expediture in your diet
It depends on your body and activity levels in general. I personally walk all the time to classes since I am an undergraduate so I dont do any additional cardio..but I have always had natural endurance I could probably run a mile in under 6 mins still even tho I have not ran for years. But I focus mainly on my weight workouts and that gets my heart rate up by itself. So I personally do not do cardio. But yes if you decide to do cardio as said above you need to up your calories...which is not fun if you need to get 4000 w/o cardio.