Warm-Up Sets: How to Work Up to the Bar
A warm-up is not an opening ritual but part of the session's design. Too little and the first work set is wasted; too much and it is already fatigued — and both mistakes are avoidable with a few percentages.
Programs specify the work precisely: five sets of three at 82.5 %. What happens before that is usually left to the lifter, even though it decides whether the first work set is any use at all.
Here is the principle, and a few ready-made schemes.
Three jobs
Warm-up sets do three different things, and it helps to keep them separate, because each asks for something different.
1. Preparing tissue and joints. Muscle temperature rises, joints travel through the range, and the nervous system wakes up to producing force. This takes little work and happens fast.
2. Rehearsing the movement. This is the underrated job. Light sets are the chance to do the lift exactly right before the load starts dictating the technique. If you are still hunting for foot position or grip width during the first work set, that set is partly wasted.
3. Measuring the day. The third warm-up set tells you surprisingly accurately what kind of day this is. If 70 % moves slower than usual, the working load is worth reconsidering before the bar is on your back.
One thing a warm-up is not: training volume. Warm-up sets do not count toward the workload, and they do not count toward the reps in Prilepin's chart either.
In fairness, one common justification deserves to be put in proportion: the evidence that warming up prevents injuries is weaker than generally assumed. The strongest case for it is performance and technique — both measurable and immediate.
The basic pattern: load rises, reps fall
Every workable warm-up scheme follows the same shape. The weight climbs in steps toward the work set, and the reps come down at the same rate.
The reason is straightforward. At light loads reps are cheap and buy you movement practice. At heavy loads every rep costs something, and the purpose is only to acclimatise to the weight — not to do work.
The most common mistake is making warm-up sets too long. Ten reps at 70 % is not a warm-up, it is a heavy work set, and it shows up immediately in what is left afterwards.
Three ready-made schemes
Moderate day, work sets at 75–85 %
| Set | % of max | Reps |
|---|---|---|
| 1 | Empty bar | 8–10 |
| 2 | 40 % | 5 |
| 3 | 60 % | 3 |
| 4 | 70 % | 2 |
| Work sets | 75–85 % | per program |
If the work set is nearer 85 % than 75 %, add one more single at 78 %. Otherwise the jump from the last warm-up into the work set is too big.
Heavy day, work set at 90 % or above
| Set | % of max | Reps |
|---|---|---|
| 1 | Empty bar | 8–10 |
| 2 | 40 % | 5 |
| 3 | 55 % | 4 |
| 4 | 70 % | 2 |
| 5 | 80 % | 1 |
| 6 | 88 % | 1 |
| Work set | 90 %+ | 1–3 |
Light day, work sets under 70 %
An empty bar and one or two intermediate sets is enough. At light loads the warm-up can be short, because the work set is already close to warm-up territory.
The rule behind all three: the heavier the work set, the more steps. The number of steps depends not on time but on how far it is from an empty bar to the working load.
How 5/3/1 handles it
5/3/1 is one of the few programs that writes the warm-up out. It prescribes three sets: 40 % × 5, 50 % × 5 and 60 % × 3.
One detail matters: those percentages are of the training max, which is 90 % of the real one. In terms of true max, the warm-up is about 36 %, 45 % and 54 % — noticeably lighter than the numbers suggest.
An example. Max 140 kg, training max 126 kg. The warm-ups are 50.4 – 63.0 – 75.6 kg, in practice 50 – 62.5 – 75 kg. The calculator produces these for the whole cycle.
The scheme is deliberately light. Wendler's reasoning is that the warm-up must not take anything away from the main sets — particularly the AMRAP set, which is the program's whole measuring instrument.
Rest periods
Warm-up rests follow the same logic as the reps: short early, longer late.
- Light sets: 30–60 seconds. Long enough to change plates.
- Moderate sets: 1–2 minutes.
- Last warm-up before work: 2–3 minutes, so the first work set starts rested.
There is a problem in the other direction too. Leave more than about a quarter of an hour between the last warm-up and the work set and the benefit starts to fade. A long stretch on your phone after changing plates is the usual reason a first work set feels unexpectedly heavy.
Four common mistakes
Too many reps. Covered above, but common enough to repeat. A warm-up set must not generate fatigue.
Too big a jump into the work set. If the last warm-up is 70 % and the work set is 92 %, that is a 22 point gap. The first work set easily goes wrong for no reason other than unfamiliarity with the load. On a heavy day, keep that gap under about ten percentage points.
The same warm-up every day. A light day does not need six sets, and a heavy one does not survive on two. The scheme follows the work set, not habit.
Counting warm-ups as work. If the program says five sets, it means five work sets. The warm-ups are on top of those.
A practical note on plates
Rounding is completely free in a warm-up: a couple of kilos either way at 55 % changes nothing. Round to whatever loads fastest.
In practice that means choosing plates so you are not stripping the whole bar at every step. The plate calculator shows the load plate by plate working outward from the bar, so you can see directly which steps only need adding and which need unloading.
Summary
The warm-up prepares the body, rehearses the movement and measures the day — it does not accumulate workload. Load climbs in steps while reps fall, and the number of steps follows the weight of the work set: two on a light day, five or six on a heavy one.
Keep the last warm-up within about ten percentage points of the work set, take no warm-up set near failure, and start the work after two or three minutes of rest.
The percentages come straight from the percentage chart, and 5/3/1's warm-ups arrive ready-made in the 5/3/1 calculator.