How to spread training days evenly across a week by hand
Picking training days by habit — "Monday, Tuesday, Wednesday, Thursday, then rest" — works, but it bunches every rest day at the end of the week instead of spacing recovery between sessions. There's a plain arithmetic rule that spreads any number of days across seven as evenly as the week allows, no guessing required.
The method
Number the seven days of the week starting from 0 (so day 0 is whichever day your week starts on, day 1 is the next, and so on through day 6). For a target of d training days a week, day number i is a training day exactly when:
(i × d) mod 7 < d
Run that check for every day 0 through 6, and the days where it's true are your training days — spread as evenly as seven slots can hold d of them. Everything else is rest. mod here means the remainder after division (so 12 mod 7 = 5, since 12 ÷ 7 leaves 5 left over).
A real example: 4 training days, a Push / Pull / Legs split, starting Monday
With d = 4, check each day number 0–6 (Monday = 0):
- Day 0 (Mon):
(0 × 4) mod 7 = 0, and0 < 4— training. - Day 1 (Tue):
(1 × 4) mod 7 = 4, and4 < 4is false — rest. - Day 2 (Wed):
(2 × 4) mod 7 = 8 mod 7 = 1, and1 < 4— training. - Day 3 (Thu):
(3 × 4) mod 7 = 12 mod 7 = 5, and5 < 4is false — rest. - Day 4 (Fri):
(4 × 4) mod 7 = 16 mod 7 = 2, and2 < 4— training. - Day 5 (Sat):
(5 × 4) mod 7 = 20 mod 7 = 6, and6 < 4is false — rest. - Day 6 (Sun):
(6 × 4) mod 7 = 24 mod 7 = 3, and3 < 4— training.
Four training days land on Monday, Wednesday, Friday and Sunday — one rest day after every training day, with the pattern wrapping cleanly from Sunday back to Monday. Naming them in a three-way Push / Pull / Legs rotation in that same order gives: Mon Push, Wed Pull, Fri Legs, Sun Push (the rotation keeps going where it left off, so the next Tuesday–Wednesday–Friday cycle continues Pull, Legs, Push).
A real example: 5 training days, a five-way split
With d = 5, the same check places training days on Monday, Wednesday, Thursday, Saturday and Sunday, with rest on Tuesday and Friday — the two rest days land roughly a third of the way and two-thirds of the way through the week rather than both sitting together. Naming a five-focus rotation (Push, Pull, Legs, Upper, Lower) against those five days in order gives Mon Push, Wed Pull, Thu Legs, Sat Upper, Sun Lower.
Why not just count from one end?
Training "Monday through Thursday, rest Friday through Sunday" also gives four training days a week, but it clusters three rest days back to back and delivers four training days back to back — the opposite of recovery spread through the week. The (i × d) mod 7 < d rule is the same kind of even-spacing logic used to lay out evenly spaced ticks on a ruler or frames in an animation; applied to a 7-day week it keeps the gap between any two rest days as close to equal as whole days allow.
What this can't tell you
This is a calendar rule, not a training programme. It decides which days you train and which you rest — it says nothing about which exercises, how many sets or reps, how much weight, or whether a given split is a good fit for you. If you're new to training, pregnant, or returning from injury or illness, talk to a qualified coach or clinician before starting a new schedule; nothing here is medical advice.
Run your own numbers
The free Workout Split Planner takes a split, your training days per week and a start day, and lays the whole thing out as a week-by-week calendar automatically, entirely on your device.