That is a solid plan, but I'd recommend adding something for hip extension, like a deadlift or back bridge. That will hit most of what you're missing in your routine.
Three days of rest for each exercise is likely too much to be optimal. Bodyweight exercises are very easy for the body to recover from, and don't require that much time. If you paired an upper body, lower body, and core exercise (ie squat/pushup/situps and deadlift/pullup/super man) and did that on a two day cycle, you'd probably experience just as much benefits in a shorter time frame.
Thanks for those exercise suggestions! I'll add back bridge to the routine coupled with squats so that I can still use the software. This is not completely necessary since squats and supermans target hip extensors a bit too if done correctly. Adding some calf exercise in the leg day might make sense too, and some flank exercise on sit-ups day.
I agree one rest day might be enough if you're not a complete beginner, rest needs vary. The problem is, the exercises become longer, and I might have to eat more to recover faster. Doing one exercise a day just after waking up is so trivial the habit is easier to keep.
Do you know any good body weight exercises for deltoids?
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