5/3/1 BBB vs FSL: Which Supplemental Work to Run

Both are free in Hardy, with every set worked out from your Training Max. Open the Boring But Big routine or the First Set Last routine.

What supplemental work is in 5/3/1

Every 5/3/1 session has three layers:

• Main work: three rising sets of the day's lift. The last one is an AMRAP, which means as many reps as you can do with good form.
• Supplemental work: a bigger block of the same barbell lift for volume.
• Assistance work: 25-50 easy reps of chin-ups, rows, leg raises and the like.

The main work never changes. The supplemental work is where the templates differ. Boring But Big (BBB) and First Set Last (FSL) are the two that almost everyone runs.

Every percentage in both is of your Training Max. That is 90% of the most you can lift for one rep, never the full amount.

BBB vs FSL side by side

What 5/3/1 First Set Last is

First Set Last means you go back to the weight of your first work set once the main work is done. You then lift it for 5 sets of 5. That weight is 65% of your Training Max in week 1, 70% in week 2 and 75% in week 3.

Wendler introduced it in Beyond 5/3/1 and made it the base of most of his later programs. Week 4 is a deload with no FSL sets. Hardy's 5/3/1 First Set Last routine has all four weeks ready to run.

When BBB is the right call

BBB exists to make you bigger. Fifty reps of squats after your main squat work is a blunt tool for hypertrophy, which means muscle growth. It works because it is boring: same lift, easy weight, no decisions.

It also builds work capacity, the amount of training you can recover from. That pays off later at heavier percentages.

Run BBB when size is the goal, you eat at maintenance or above, and you can afford the soreness. Start at 50% even if it looks light, because across five sets of ten it is not. The 60-70% versions are for lifters who have handled 50% for several cycles.

When FSL is the right call

FSL keeps the bar heavy enough to feel like a work set, at 65-75% of your Training Max instead of 50%. Every rep is practice for the main lift, at half the rep count.

That makes it the pick when strength comes first, when you are cutting, or when sleep and stress are working against you.

You give up some size stimulus. You keep the skill work and most of the strength signal. Your week 3 AMRAP sets also tend to stay strong, because you walk into them less beat up.

Switching between them cycle to cycle

• The main work, the Training Max raises and the week 4 deload are identical, so you can swap BBB for FSL between any two cycles.
• A common pattern is seasonal: BBB cycles while you build through winter, FSL cycles while you cut for summer.
• Another is blocks: two or three cycles of BBB for size, then one or two of FSL to get used to heavier weights.
• Whatever you pick, keep it for the whole cycle. One hard week tells you nothing about a template.