What is Boring But Big?
Boring But Big (BBB) is the best-known 5/3/1 template for building muscle. Each session has two parts. First you do the day's main lift for the standard 5/3/1 working sets - three sets, with the last one taken for as many reps as you can. Then you do five sets of ten of a supplemental lift at a light, fixed percentage of your training max, followed by a small amount of assistance work.
The name is honest. Fifty reps of squats or deadlifts at the same weight is boring, and it is the volume, not the intensity, that makes you bigger. It is run four days a week, one main lift per day: overhead press, deadlift, bench press and squat.
The calculator above builds the whole cycle for you. Enter a recent hard set for each lift, choose your BBB percentage and whether the 5×10 uses the same lift or its opposite, and every weight is worked out and rounded to what you can load.
Choosing the BBB percentage
The original prescription is 50% of your training max, and that is where almost everyone should start. Fifty reps at 50% sounds easy on paper. Squatting it after three heavy sets, four days a week, is not, and the first cycle is mostly about building the work capacity to recover from it.
Once 50% is comfortable there are two common ways to make it harder:
- Raise the percentage each cycle. A well-known three-cycle progression takes the 5×10 from 50% to 60% and then 70%. By the third cycle the supplemental work is genuinely heavy, which is why it is usually paired with 5s PRO on the main lifts rather than AMRAP sets.
- Hold the percentage and let the training max do the work. Because the 5×10 is a percentage of your training max, it goes up automatically every cycle. Many lifters stay at 50-60% for a long time and still grow.
The calculator offers 40% to 70%. Going above 70% for five sets of ten is not BBB any more - it is a different, much harder programme, and the main work would suffer.
Same lift or opposite lift?
There are two ways to pick the supplemental lift, and both are legitimate:
- Same lift. Squat day is squats for the main sets and squats for the 5×10. This is the original version. It gives you the most practice at each lift and is the simpler choice if technique is your limiting factor.
- Opposite lift. Squat day pairs with deadlift 5×10, deadlift day with squat, bench with overhead press and press with bench. Each lift is then trained twice a week, and the lighter 5×10 acts as a second, easier session for it. Many people find this less draining, particularly on deadlift day, where 5×10 deadlifts at 50% after heavy pulls can wreck the rest of the week.
The calculator defaults to the opposite lift. If you switch to the same lift, the deadlift 5×10 is the set to watch - keep it at 50% until you are certain you recover from it.
Assistance work and conditioning
BBB already contains a lot of volume, so assistance is kept deliberately small: one pulling movement or one core movement per day, five sets of ten. The calculator uses lat pulldowns and barbell rows on pressing days and hanging leg raises on the lower-body days. Chin-ups, dumbbell rows, face pulls and ab wheel work are all fine substitutes. What you should not do is bolt a bodybuilding routine onto the end of it.
Keep conditioning easy while you run BBB. Walking, sled drags, light bike work. Hard conditioning on top of 5×10 squats is the fastest way to stall.
Who BBB is for
BBB suits lifters who want to add muscle and are willing to eat enough to do it. It is a poor choice on a strict diet: the volume is high, recovery is the whole game, and you will feel it within two weeks if you are under-fed.
It works best when your training max is set honestly. Use 85% of your estimated 1RM, not 90%, for the first cycle. The main sets are supposed to leave enough in the tank to get through the 5×10, and a training max that is too high is the most common reason BBB feels impossible.
Plan to run it for two or three cycles, then move to something with less volume - First Set Last is the usual next step - before coming back to it. In the leader and anchor approach, BBB is a leader: run it with 5s PRO for two cycles, then anchor with a lower-volume template and PR sets.
Common mistakes
- Starting above 50%. The 5×10 is meant to be light. Earn the right to raise it.
- Setting the training max too high. If your AMRAP sets are barely hitting the minimum reps, everything after them suffers. Drop the training max to 85%, or lower.
- Resting too long between the 5×10 sets. Sixty to ninety seconds is plenty. Longer rests turn a thirty-minute session into an hour and remove much of the conditioning effect.
- Adding assistance. A pull and some core work, that is all. Extra curls and flyes are not what is holding you back.
- Running it too long. Three cycles is about the limit before the volume stops paying off and starts costing you. Switch templates, then come back.