A workout split divides your training week so each session trains part of your body rather than all of it. Three structures actually hold up: upper lower, push pull legs, and the classic one muscle group per day. Choosing between them comes down not to which is best in theory but to how many days a week you genuinely make it to the gym. Below is each one, plus when a split is worth its complexity and when it only gets in the way.
The rule that decides everything: frequency
Before picking a structure, you need the yardstick to compare them by. There is one: how many times a week each muscle group gets trained.
The meta-analysis on training frequency shows that weekly volume per muscle is what drives growth, not how many days you spread it across. But there is a practical caveat: accumulating enough volume in a single weekly session is physically hard, so it is easier to split across about two. That gives the benchmark everything below is judged against: each muscle group trained roughly twice a week.
That, rather than fashion, is why the classic “Monday chest, Tuesday back” loses to upper lower at the same number of sessions.
The three that work
Upper and lower
The body splits in half: one session for upper, one for lower.
| Day | What you train |
|---|---|
| Monday | Upper: chest, back, shoulders, arms |
| Tuesday | Lower: quads, hamstrings, glutes, calves |
| Thursday | Upper |
| Friday | Lower |
At four sessions, every group gets trained twice a week. It is the simplest way to hit the benchmark, which is why upper lower is the default recommendation for anyone who has outgrown full body.
It survives on three sessions too: days alternate week to week (upper, lower, upper, then lower, upper, lower), landing at one and a half sessions per group per week.
Push, pull and legs
The body splits by movement type: everything you push, everything you pull, and legs on their own.
| Day | Movements | What works |
|---|---|---|
| Push | Bench press, overhead press, extensions | Chest, shoulders, triceps |
| Pull | Pulldowns, pull-ups, rows, curls | Back, biceps |
| Legs | Squat, leg press, Romanian deadlift, calves | Whole thigh, glutes, calves |
The logic is that muscles already working together get trained together. Your triceps take part in the bench press anyway, so there is no sense giving them their own day.
At six sessions a week each group is trained twice. At three sessions frequency drops to once, and the structure loses its advantage: three days a week is better served by upper lower or full body.
The classic bro split
The famous one: chest and triceps, back and biceps, legs and shoulders.
It came from bodybuilding, where the athlete has the years, the experience and the need for very high volume per muscle. At three sessions a week each group is trained once, half the benchmark. For most people it is the weakest of the three, even though it subjectively feels the most correct: a whole session devoted to one area, with a pump you can really feel.
That pump is not a measure of growth, though, it is blood flow. It is not a reason to pick a structure.
Which split fits your schedule
Work from the honest number of sessions you hit, not the one you plan.
| Sessions per week | What to run |
|---|---|
| 2 | Full body, no split needed |
| 3 | Full body, or upper lower alternating |
| 4 | Upper and lower, the best balance of frequency and volume |
| 5 | Upper lower plus a day for a lagging group |
| 6 | Push pull legs run twice |
Honest is the operative word. A six-day plan you attend three times a week performs worse than a three-day plan you complete. Splits are more sensitive to missed sessions than full body: skip leg day on push pull legs and your legs get nothing all week, while skipping one full body session costs you a third of everything.
When a split is the wrong answer
Your first months in the gym. While you are still learning the movements, repetition matters more than volume per group. Beginners want full body three times a week, covered in the article on the beginner workout plan.
Coming back after time off. The first weeks back run at low load by definition, so there is nothing to divide up. How to set starting weights is covered in the article on getting back to the gym.
An unpredictable schedule. If weeks vary and you cannot say in advance whether you will make it twice or four times, full body is safer: every session stands on its own, and a missed one never leaves a muscle group untrained.
How to build your own split
- Count how many sessions a week you have genuinely managed over the last month.
- Pick the structure from the table above.
- Put 5 to 7 exercises in each session: compound barbell and dumbbell work first, machines and isolation after.
- Accumulate 10 to 20 working sets per muscle group per week across all sessions.
- Hold the structure for at least 8 to 10 weeks, otherwise you never learn whether it worked.
- Log weights and reps: without a record there is no way to tell whether load is going up or standing still.
The one rep max calculator helps you set working weights for a new structure, and the warm-up sets calculator builds the ladder up to them.
In short
- A split earns its place at four sessions a week and up; below that, full body.
- The benchmark for choosing: each muscle group trained about twice a week.
- Four sessions, run upper lower. Six sessions, run push pull legs.
- The classic one group per day gives once-a-week frequency and loses for most people.
- Pick for the honest session count, not the aspirational one.
- Do not change structures for at least 8 to 10 weeks.
APX builds a split around the number of days you specify, fits exercises to the equipment you have, and logs every set so weekly volume is something you can see in numbers rather than estimate.