I am using and upper/lower split. My lower back gets worked when doing squats and deadlifts. A bit less with SLDL, Lunges, Standing Military Press, Bent Over Rows.
I was thinking, that if I perform 3 sets of ab work on both lower body days, I should do 3 sets of back extensions (like for balance, antagonist muscles). But then I thought about all the work it gets and if I do special work, back extensions, it might be too much? And if I will overtrain my lower back, then my squat and deadlift poundages wont go up either.
So I wanted to know, if other people do them or not? What do you think about them, are they useless or do they help making lower back stronger?