I have a hard time eating right before bed and then agaion when I wake up unless I do cardio............plus, it keeps me lean through bulking stages..........never over 10%
I go 2 or three times a week, 20-30 minutes, med intenstity post workout. Then I run for 30 minutes on one off night per week. So far that seems to be balancing out my atrocious diet of late.
I'm cutting currently and diet is definitely more important than how often I do cardio...cardio just gives you that extra boost and keeps your lungs/heart in shape.
My cardio schedule is:
3x per week - hardly ever on a lifting day - and even then 8 hours after lifting. Depending on my schedule I aim for either 20min of high intensity intervals or an hour of medium intensity. I also started going to a spinning class once a week.