My standard split in general is Monday, Back and chest. Wednesday is legs. Friday is delt and arms then two days off. It works well for me. I know many will say you need to work out body parts more than once a week but I do because of over lap. On back day all the pulling is getting biceps hard. No way from a kinesiology analysis can you avoid the bicep involvement. On Friday biceps gets hit directly again on arm day. Another example is legs get their own day on Wednesday but on back day Monday they are hit hard when I do either power cleans or deadlifts. On it goes. Triceps are being hit hard on chest day with the pushing on Monday and again hit on arm day on Friday. I could go on for each body part but you get the drift.
I enjoy hitting a body part with several different exercises to use exercises that work mid range, stretch and the contracted position. An example is dips or close grips for midrange triceps, Single dumbbell behind the neck with two hands for stretch position and something like two hand kick backs to emphasize the contracted position.
The split I use the majority of the time also gives me four days off. On two of those days I try to get a run in with some boxing drills that I enjoy.
I really enjoy hearing how others work out whether it's cross fit, running, martial arts, body weight or weight training. I see the swing in weight training today seems to be away from the standard 8 to 12 reps into high reps. I understand why many are going to it. It can be really brutal. I think the guy leading the way for this is this youtuber Ryan Humiston. He said in effect that adding weight to do a set of 8 is easier that trying to do four sets of 20 with little rest between sets. He sometimes does a single century set (100 reps) and that sounds brutal. He gives the example of how he sometimes does that with squats or hacks. I saw a couple of videos of the pro Kai Greene that uses high reps. On the video I watched he did three sets of an exercise hitting 20 reps on set one. Around 15 reps on set two and around 12 reps on set three. I'm sure some would argue that what ever a drug using guy does in the weight room isn't proof of a valid training protocol. If intensity was the magic bullet of training we would all be doing something like 4 sets of one rep after warm up. That's the most intense training we could do. I think Humiston might be on to something. Maybe muscular endurance is the magic bullet of muscle growth.