Wendler 5/3/1 Explained
Created by Jim Wendler, 5/3/1 is a strength program built on a simple philosophy, which is to start lighter than you think you should and progress slowly so you can keep progressing for a very long time. It is one of the most popular intermediate programs for good reason.
Start with your training max
Everything in 5/3/1 is calculated from a training max rather than your true one-rep max. Your training max is set at around ninety percent of your best single, and using this slightly conservative number is the whole trick, because it keeps the working weights manageable and leaves room to grind out extra reps. The four main lifts are the overhead press, deadlift, bench press, and squat, each trained once per week.
The four-week cycle
Each training cycle runs four weeks, and every week prescribes three working sets at rising percentages of your training max.
Week 2: 70% x3, 80% x3, 90% x3+
Week 3: 75% x5, 85% x3, 95% x1+
Week 4 (deload): 40% x5, 50% x5, 60% x5
The plus sign on the final set of each working week is the key, since that set is an AMRAP, meaning you do as many quality reps as possible rather than stopping at the prescribed number. Those extra reps are where rep records are set and where the program lets a good day pay off, while the deload in week four lets you recover before the next cycle.
How you progress
After each four-week cycle you raise your training max by a small fixed amount, typically about five pounds for the upper body lifts and ten pounds for the lower body lifts. Because the jumps are small and tied to the conservative training max, progress feels almost too easy at first, which is exactly the point, since slow and steady advances accumulate into large gains across many cycles.
Assistance work
The main lifts are the skeleton, and 5/3/1 is usually paired with an assistance template that fills in muscle and work capacity. Boring But Big, which adds five sets of ten on the main movement, is one of the best known, and there are many others depending on whether your goal leans toward size, conditioning, or pure strength.
If you want more volume and faster weekly progress, nSuns 531 LP is a popular high-volume fork of 5/3/1: it keeps the training max and the AMRAP top set, but runs a nine-set main lift plus an eight-set second lift five days a week and raises your training max every week instead of every month. It is a bigger commitment, and a natural next step once 5/3/1 starts to feel light.
Running 5/3/1 in Ægir Iron
5/3/1 runs on percentages, so on paper the friction is doing the math for every set and tracking a training max that keeps climbing. Ægir Iron ships 5/3/1 as a pre-built program you load in a couple of taps and then make your own. You choose whether your saved number is a true one-rep max, in which case the app takes ninety percent for your training max, or a training max you have already set, and whether to add Boring But Big, the five-sets-of-ten supplemental, after the main work. Pick which of the four lifts get a day and load it, and the app prices every working set from your training max, rounds each to the nearest five pounds, and flags the plus set as an AMRAP.
You do not need a tested max to start. If you have not set one, add a quick estimate as you load the program, or just begin logging and the app suggests a starting weight from your own history, a related lift, or your bodyweight. Each four-week wave is its own cycle, so when you finish one Ægir Iron prompts you to advance, using the AMRAP reps you logged to size each jump, and the next wave reprices itself. Log your sets and your rep PRs update automatically.