why train more than 3 times in a week?

[Whiskey]

Mon : Squats 8 sets, Narrow stance squats with 3 second pause in the hole 2 sets.
         1 leg leg press 2 sets 10 reps
         Leg extension  2 sets 10 reps
         Leg curl 3 sets 10 reps
         Seated calf raise 3 sets 12 reps
         25 min stretching

Wed : Bench press 8 sets, Close grip bench press with 2-3 second pause on chest 2 sets, Barbell Incline Press with pause on chest 2 sets
         Ab work
         Standing Calf Raise 3 sets 10 reps
         25 min stretching

Fri :   Deadlift 8-10 sets
        Stiff leg Deadlift off block 2 sets
        Barbell row 2 sets 8 reps
        Pullup 2 sets (whatever I can do)
        Lat pulldown 1 sets 12reps
        Seated Calf raise 3 sets 12 reps
        Ab work
        25 min Stretching

[T-REX007]

I have known some really big guys - mostly body builders that did the 1 body part a week thing - split M-F, and looked pretty good- they were natural, too. Not freaks, but really good physiques - 25'' quads, 18'' arms etc.. and the guys I am thinking of right now were in the 225- 230 range, they are  definitely OCD though when it comes to the gym - they said 3 x  a week wasn't enough for the "next level"

Honestly though, I don't know how you wouldn't burn out going balls to the wall 5 days a week, but these guys do it year after year

I have also known a few powerlifters that trained pretty much 5 x a week, these were specialists though - one guy was a bencher and the other a squatter, they both swore high volume training was by far the best way to go for strength gains, not so much size though.

[jude2]

the freakish bbers workout each muscle once a week typically when trying to build size

Young man. The 3 greatest BB of all times trained each muscle groups 2-3 times a week. Arnold, Lee H and Ronnie C.

[the trainer]

Three full body routines per week. Conditioning on off days.

split body parts and condition on the same day and on your off day you just rest, stop overtraining your clients.