So how many sets in those 5 hours did you think you did?
Arm day was 50 total sets. That was 2 to 2.5 hours for the second workout of the day which was arms, calves and abs. Chest and back were much the same. Some days I would do those crazy fast "giant sets" of five bicep or tricep exercises in a row and then rest/repeat for a total of 25 sets for each. I thought I would puke. If memory serves, I think I did a few times.

I pretty much did calves and abs every day. Stupid, huh? Shoulders were done in the mornings along with ab and calf work. I was overdoing it but I thought that was the way it was done and did so for years.
Thighs were done alone except for ab and calf work. I was so crazy to get as big as I could. I ate tons of food and even drank whipping cream for the calories. Squats were my favorite and I got quite good at them. Same with what we all called the "real leg press" (inverted). I really enjoyed leg pressing on the inverted machines. Much better than those angled jobs.
I hated doing legs until some of my powerlifting friends introduced me to the 20 rep set routine and from that moment on it was my favorite exercise, bar none. Was I training hard? On leg day, no doubt. The other days I now think I trained pretty damn hard but I over trained too. I did get to 250 lbs but my size was nowhere near my friends on steroids. Also my bodyfat was probably in the low 20% range. Again, nothing like a competitive bodybuilder although I did compete a few times. I was not good enough but I was no Genova,LOL!
Today was a total of 4 sets back and 4 sets of chest. That would include a couple of warmup sets for each body part before doing the pre-exhaust isolation movement followed by the compound one. I train at home most of the time but have considered joining a gym. I fear I would get envious and at my age, I cannot afford a new kidney. Dammit!

Sometimes I get out the 2.75" bar for curls but not very often now. It bothers my elbows. I am far from well built but I am still training and that is what matters. My ego gets in the way every now and then but that's to be expected. I watched the Mentzers train in the late 70s at Gold's. They and Viator trained brutally hard or at least the few times I saw them. Impressive.