I really like using supersets/giant sets/circuits, so upper-lower splits or full-body workouts have always worked well for that. For the last two months or so, I’ve been doing full-body circuit stuff 4 days a week and it’s brutal and awesome and, yeah, a little fun.
A complete 180 on that, I also really like just one lift a day, usually with EMOM. Something to be said for just going balls out on one big exercise and calling it a day to help dial in the focus and bring the intensity.
Not to speak for fitafter40, but two weight training sessions a week can be great if you’re active doing other stuff throughout the week, like he said he does. That’s why it’s a solid approach for in-season athletes, for example, who have other training and practices to get through during the week.
But it can also depend on your goals. Like, for fat loss, two sessions per week wouldn’t be ideal because you’ve got to be that much more dialed in on the nutrition front since you’re not expending as much energy in training. For putting on size though, I’m pretty sure the old 20-rep squat routine had a two-day a week option. So it can definitely be made to work on that front.
Or, for guys with manual labor jobs who’re moving bricks and whatnot 10 hours a day five days a week, tacking on another 5 hours of lifting weights isn’t always the best idea there, so hitting the gym twice over the weekend can avoid overtraining allow some recovery.