Lee Haney's Old School Push/Pull.

A four-day rotating cycle: three training days, one rest day, then start again. Each upper-body day pairs a pushing muscle with a pulling one, legs get their own day, and abs and calves are hit twice per cycle. Because the cycle is four days long it drifts through the calendar — day 1 will not always be a Monday, and that is the point. Run it continuously. Based on the split Lee Haney describes in the video linked below; this program is not affiliated with or endorsed by him, and the exercise selection, sets, reps and rest here are our own. Note: the source describes push as chest and pull as biceps, then back and shoulders, and does not say where triceps go — they are placed with shoulders on day 3, since both are pushing muscles and that keeps the push/pull pairing intact on both upper days.