Sergi Constance's arm workout isn't a separate arm day. Biceps close out his two pull days with three curl variations, and triceps are trained on his two push days with a close-grip press, dips or push-ups supersetted with the flat dumbbell press. Every exercise runs as a 15-to-8-rep pyramid, and the weight goes up 2.5 kg (5 lb) when you complete every rep.
Below is exactly what that looks like, how much weekly volume it adds up to, how to perform each lift, and how to keep progressing on small dumbbell movements where load jumps are awkward.
Where arms fit in his split
Sergi's plan is a 6-day split in a fixed order: legs (quads), push, pull, legs (hamstrings), push, pull, rest. Arms piggyback on the days where they're already working.
| Day | Session | Arm work |
|---|---|---|
| Days 2 and 5 | Push: chest, shoulders, triceps | Triceps superset + every press |
| Days 3 and 6 | Pull: back, biceps, abs | Three curl variations + underhand back work |
Each arm muscle gets trained twice a week, which lines up with the frequency research: Schoenfeld, Ogborn and Krieger's 2016 meta-analysis found more growth from training a muscle at least twice a week than once.
The biceps workout (pull days)
After the back work, the pull day finishes with this block:
| Exercise | Sets | Reps |
|---|---|---|
| Standing dumbbell curl (alternating or both arms) | 5 | 15 → 8 |
| Preacher curl or concentration curl + superset | 4 | 15 → 8 |
| ↳ Dumbbell hammer curl | 4 | 15 → 8 |
The pyramid runs 15, 12, 10 and 8 reps, adding weight each set; on the 5-set curl, the fifth set repeats 8 reps with the set-4 weight. In the superset, do one set of preacher or concentration curls, go straight to hammer curls, then rest 60 to 90 seconds.
The biceps are already warm when you get there. The pull day opens with chin-ups or an underhand lat pulldown and an underhand barbell row. Palms-up pulling loads the biceps heavily, so by the first curl they've done 9 sets of compound work.
Why three curl variations
- Standing dumbbell curl: the heaviest curl of the day and the main loader. Supinate (turn your pinky up) as you lift to fully engage the biceps.
- Preacher or concentration curl: your upper arm is braced, so you can't swing. The preacher bench also loads the biceps hardest near the bottom, where the muscle is stretched.
- Hammer curl: the neutral grip shifts more of the work to the brachialis and brachioradialis. A bigger brachialis pushes the biceps up and adds thickness to the arm, seen from the front and the side.
The triceps workout (push days)
| Exercise | Sets | Reps |
|---|---|---|
| Flat dumbbell press + superset | 4 | 15 → 8 |
| ↳ Close-grip press (dumbbell or barbell), dips or push-ups | 4 | 15 → 8 |
That's the only exercise in the plan aimed squarely at the triceps, which surprises people. The reason is everything around it. Every push day includes an incline press, a flat dumbbell press and a shoulder press, and the triceps extend the elbow on every rep of all three. Pair the close-grip work directly with the flat press and you hit the triceps when they're already pre-fatigued, so a moderate load does a lot of work.
Pick the variation that suits your setup and your joints:
- Close-grip press: with a barbell, hands about shoulder-width, not touching. With dumbbells, palms facing each other, pressing them together. Elbows stay close to your sides.
- Dips: keep your torso upright to shift work onto the triceps; leaning forward turns them into a chest exercise. Go down until your upper arms are about parallel to the floor, not deeper if your shoulders complain. Add weight once body weight gets easy.
- Push-ups: hands under your shoulders or slightly narrower, elbows tucked. Elevate your feet to make them harder.
Weekly arm volume
| Muscle | Direct sets per week | Indirect work per week |
|---|---|---|
| Biceps | 26 (13 per pull day) | Chin-ups/pulldowns + underhand rows: 18 sets |
| Triceps | 8 (4 per push day) | Incline, flat and shoulder presses: 24 sets |
The research consensus puts the most productive range for most lifters at 10 to 20 sets per muscle per week. Biceps direct volume here sits above that, which is fine for trained lifters who recover well, and too much for someone just starting out. Triceps get less direct work but a lot of heavy compound work, which is where they do most of their growing anyway.
How to progress
- Log every set: weight and reps.
- If you completed every prescribed rep last time, add 2.5 kg (5 lb).
- If you fell short, repeat the same weight until you hit it.
On arm exercises, that jump can be a big percentage. Going from 12 to 14 kg (about 25 to 30 lb) dumbbells is a jump of nearly 17%. If you can't complete the pyramid with the heavier pair, keep the current weight and add a rep or two per set first. When your 8-rep set turns into 10 clean reps, the next pair will be manageable. On cable or machine variations, where the stack moves in smaller steps, use the smallest jump available.
Keeping track of all this across five curl and press variations is where most people lose the thread. In Boost, every set shows what you lifted last time and your target for today, so the progression rule is applied for you.
Technique mistakes that cost arm growth
- Swinging the curl. If your hips and shoulders move, the weight is too heavy. Elbows stay pinned at your sides.
- Cutting the bottom short. Lower all the way until your arm is nearly straight. The stretched position is where curls do a lot of their work.
- Flaring your elbows on close-grip work. Elbows out turns it into a chest press and stresses the shoulder.
- Rushing the superset. Moving straight into the second exercise is the point, but each rep still gets full control.
- Going heavy on set 1. The 15-rep set is the warm-up for your elbows. Elbows don't like being surprised.
Choosing your weights, tempo and rest
Pyramids only work if each set is loaded right. Use this as a guide for both the curls and the close-grip work:
| Set | Reps | How it should feel |
|---|---|---|
| 1 | 15 | Easy: 3 to 4 reps left in the tank |
| 2 | 12 | Moderate: 2 to 3 reps left |
| 3 | 10 | Hard: 1 to 2 reps left |
| 4 (and 5) | 8 | Close to failure, form still clean |
Lift in about one second and lower in about two. A controlled lowering phase keeps tension on the muscle and is easier on the elbows than letting the weight drop. Rest 60 to 90 seconds between curl sets and after each superset round; the flat dumbbell press is a compound lift, so if you need closer to 2 minutes after that pair, take it.
Bigger arms also need food
Arm size follows overall muscle gain. If your body weight hasn't moved in months, your arms probably haven't either, no matter how well you curl. To build muscle you need enough protein, about 1.6 to 2.2 g per kg of body weight a day (roughly 0.7 to 1 g per lb), and a small calorie surplus of around 200 to 300 kcal a day. We don't publish what Sergi eats, and his intake wouldn't fit your body anyway: in Boost, the diet is set for each person.
If you're newer to lifting
With under about 6 months of training, cut each exercise to 3 sets (15, 12, 10 reps). For biceps, keep the standing curl and the hammer curl and drop the preacher curl; for triceps, keep the superset as is. After 8 to 12 weeks, when your weights stop climbing easily, move to the full volume.
Arms finish the pull day, but the session ends with abs. That superset is broken down in Sergi Constance's abs workout.