Ya, lower back. You should not combine major compound exercises on the same day. For one thing you're sub-optimal due to fatigue on the second compound, and further they're not a primary leg movement. One 4-split option: Back/bicep (DLs, rows or pullups), curls off Chest/tri (alternating wide and narrow bench), weighted dips off Legs (Squats) off Abs/shoulders/traps (abs), overheads, rack cleans (3 sets max) (off) on day 8. Offers a bit more rest
Ok. Well, I don't do squats and deads on the same day, anyhow. My back (mid and lower) is really sore. My legs, not at all. Thanks, dude.
You'll need a cage. This is decent for home use. http://www.amazon.com/Bodycraft-F430-BodyCraft-Power-Rack/dp/B0007QDLCQ
Cool. I use the cages at my gym for squats. I set the safety pegs just above a full ATG. The barbell deadlifts, I do straight off the floor. Good or bad?
Ya, me too. Atticus, how do you ensure you don't injure the lower back on deadlifts? Is there any particular trick or critical tweak I should be aware of?
Don't lift beyond your ability. Warm up, good form, straight back. Stay clear of stiff leg exercises. I would start with rack pulls.