What are the best exercises for building bigger arms?

The best exercises for arm hypertrophy are curls for biceps (dumbbell curls, EZ bar curls, cable curls) and isolated tricep extensions for triceps (cable pushdowns, skull crushers, overhead cable extensions). These isolation movements train all heads of each muscle group most effectively.

Do back exercises like rows fully train the biceps?

Not fully. Because the biceps brachii is a biarticular muscle, rows and pull-ups cause it to shorten at the elbow but lengthen at the shoulder simultaneously. This creates opposing muscle actions that limit biceps stimulation. The brachialis benefits more from pulling movements since it only crosses the elbow joint. Direct curl work is still needed for complete biceps development.

Do compound pressing exercises like bench press train the triceps effectively?

Pressing exercises train the lateral and medial heads of the triceps reasonably well since they only cross the elbow joint. However, the long head is not maximally trained because pressing involves shoulder flexion while the long head performs shoulder extension. This creates opposing actions that limit long head recruitment. Dedicated tricep extension work is recommended for full development.

Should I supinate my wrists during bicep curls?

Yes, when using exercises that allow free wrist rotation like dumbbell curls. Start with a neutral grip at the bottom and rotate your palms to face upward at the top. Because the biceps brachii performs forearm supination, this technique adds slightly more range of motion and stimulus to the muscle.

How to Train Your Arms for Hypertrophy: Biceps & Triceps Guide

Most lifters want bigger arms.

And most of them are leaving serious growth on the table because of how they train.

Not from a lack of effort. From a lack of understanding.

Your arms aren't just one big slab of muscle you hammer with curls and pushdowns. They're a collection of individual muscles with different anatomical structures, different functions, and different training requirements.

Get those details wrong, and you'll spin your wheels for years.

Get them right, and you'll build arms that actually match the work you're putting in.

This guide breaks down the anatomy, exercise selection, and technique for both biceps and triceps. Whether you're building muscle while losing fat or in a dedicated growth phase, the principles are the same. No guesswork. Just what the science and biomechanics actually tell us at Mesostrength about maximizing arm hypertrophy.

Anatomy of the Biceps: What You're Actually Training

Let's start with what's on the front of your arm.

The "biceps" region is actually made up of two primary muscles. And understanding what each one does will change how you think about training them.

The Biceps Brachii

This is the muscle most people picture when they think "biceps."

It has two heads: the long head (outer portion) and the short head (inner portion).

Both heads share the same basic structure. They originate on the scapula just above the shoulder joint and insert onto the radius, one of the two forearm bones.

Here's what matters: because both heads originate above the shoulder, the biceps brachii crosses two joints. The shoulder and the elbow.

That makes it a biarticular muscle. And that fact has massive implications for exercise selection.

The Brachialis

This one gets overlooked constantly.

The brachialis sits underneath the biceps brachii. It's slightly smaller and less visible, so it won't contribute as much to how your arms look from the front.

But here's the key anatomical difference: the brachialis originates on the humerus (upper arm bone), not the scapula.

That means it only crosses one joint: the elbow.

It doesn't care what your shoulder is doing. It just flexes the elbow. Period.

Muscle	Origin	Insertion	Joints Crossed
Biceps Brachii (Long Head)	Scapula	Radius	Shoulder + Elbow
Biceps Brachii (Short Head)	Scapula	Radius	Shoulder + Elbow
Brachialis	Humerus	Ulna	Elbow only

The biceps brachii is a two-joint muscle. The brachialis is a one-joint muscle. That single difference dictates almost everything about how you should train them.

Anatomy of the Triceps: Three Heads, One Mission

Now flip to the back of the arm.

The triceps brachii is technically one muscle, but it has three distinct heads. And just like the biceps, each head has slightly different anatomy that affects how it responds to training.

The Long Head

The long head sits on the inner side of the arm. It's the largest head and the one that gives your triceps that thick, hanging look from behind.

It originates on the scapula and inserts on the ulna.

Sound familiar? Just like the biceps brachii, the long head crosses both the shoulder and elbow joints. It's biarticular.

This matters. A lot.

The Lateral Head

The lateral head is on the outer side of the arm. It's the one that creates that horseshoe shape everyone chases.

It originates on the humerus and inserts on the ulna. One joint. Elbow only.

The Medial Head

The medial head sits underneath the other two. You can't really see it from the outside because the long and lateral heads cover it up.

Like the lateral head, it originates on the humerus and only crosses the elbow joint.

Triceps Head	Origin	Insertion	Joints Crossed
Long Head	Scapula	Ulna	Shoulder + Elbow
Lateral Head	Humerus	Ulna	Elbow only
Medial Head	Humerus	Ulna	Elbow only

The long and lateral heads are the two most superficial portions. They're what you actually see on a developed physique.

Two of the three triceps heads only act on the elbow. The long head acts on both the elbow and shoulder. This distinction is the foundation of smart triceps training.

How the Biceps and Triceps Actually Work

Before we get into exercises, you need to understand the movements these muscles produce.

This is where most people's arm training goes sideways. They pick exercises without knowing what their muscles are actually doing during the movement.

Biceps Movements

The biceps region produces three primary actions:

Elbow flexion — closing the elbow joint, like bringing your hand toward your shoulder. Both the biceps brachii and brachialis perform this movement.
Forearm supination — rotating the forearm so your palm faces upward. Only the biceps brachii does this. The brachialis attaches to the ulna and can't rotate the forearm at all.
Shoulder flexion — raising the arm in front of the body. Only the biceps brachii contributes here, because it crosses the shoulder joint.

Triceps Movements

The triceps produce two primary actions:

Elbow extension — straightening the arm from a bent position. All three heads contribute to this.
Shoulder extension — pulling the arm downward from a raised position. Only the long head does this, because it's the only head that crosses the shoulder joint.

Here's the pattern you should notice: the biarticular portions (biceps brachii and triceps long head) act on two joints. The single-joint portions (brachialis, lateral head, medial head) only act on the elbow.

That pattern is the entire foundation of intelligent arm training.

Every exercise you pick for arms should be evaluated based on which muscles it trains and whether opposing joint actions limit stimulation of the biarticular heads.

The Best Exercises for Biceps Hypertrophy

Here's the good news: the best biceps exercise is also the simplest one.

Curls.

Any variation where you flex the elbow against resistance with minimal movement at other joints. That's it.

Why? Because elbow flexion is the one movement that every muscle in the biceps region performs. Both heads of the biceps brachii and the brachialis all contribute to curling.

Top Curl Variations

Dumbbell curls — allow free rotation of the wrist, which lets you add supination for extra biceps brachii stimulus
EZ bar curls — a fixed grip option that's easier on the wrists while still loading elbow flexion effectively
Cable curls — provide consistent tension throughout the range of motion, including at peak contraction

What About Front Raises?

In theory, front raises should train the biceps brachii because it crosses the shoulder and assists with shoulder flexion.

In practice? Probably not worth your time for biceps.

The reason is structural. The actual contractile tissue of the biceps brachii sits primarily toward the lower portion of the muscle near the elbow. At the shoulder end, there's a much longer tendon structure.

This means the biceps has a poor mechanical advantage for shoulder flexion. The front deltoids are far better suited for that movement.

And because there's zero elbow flexion during a front raise, the brachialis gets absolutely nothing from the exercise.

Bottom line: curls are king for biceps. Don't overthink it.

The curl is the primary biceps exercise because it's the only movement category where all biceps muscles contribute maximally. There's no need to complicate this.

Why Rows and Pull-Ups Won't Maximize Your Biceps

This is one of the most common misconceptions in training.

"I do heavy rows and pull-ups, so my biceps are covered."

They're not. And here's exactly why.

Rows and vertical pulling exercises (covered in depth in our back training guide) involve two simultaneous joint actions: shoulder extension and elbow flexion.

The elbow flexion part sounds great for biceps. And it is, for the brachialis. Since the brachialis only crosses the elbow joint, it can fully contribute during pulling movements without any issues.

But the biceps brachii? That's a different story.

Remember, the biceps brachii performs elbow flexion AND shoulder flexion. During a row, your elbow is flexing (good) but your shoulder is extending (the opposite of what the biceps does at the shoulder).

This means the biceps brachii is shortening at the elbow while simultaneously lengthening at the shoulder.

Two opposing muscle actions happening at the same time.

The result: the biceps brachii can't fully shorten, can't achieve maximum contraction, and probably isn't receiving optimal mechanical tension for hypertrophy.

Think of it like trying to squeeze a spring while someone is pulling it from the other end. You're working against yourself.

Exercise Type	Brachialis Training	Biceps Brachii Training
Curls (isolation)	Full stimulation	Full stimulation
Rows/Pull-ups	Full stimulation	Compromised (opposing joint actions)
Front raises	No stimulation	Poor (weak mechanical advantage)

So yes, your back training will hit the brachialis decently. But if you want full biceps brachii development, you need dedicated curl work.

Rows and pull-ups are back exercises first and forearm flexor exercises second. The biceps brachii is caught between opposing joint actions during pulling, which limits its growth stimulus.

The Best Exercises for Triceps Hypertrophy

Just like curls for biceps, there's one primary exercise category that stands above everything else for triceps.

Isolated tricep extensions.

Any exercise that involves only elbow extension without movement at other joints. Cable pushdowns, skull crushers, overhead cable extensions. Anything where the elbow straightens against resistance and nothing else moves.

Why are these so effective? Because all three heads of the triceps contribute to elbow extension. Every single fiber of the muscle group is working during a pure extension movement.

Top Tricep Extension Variations

Cable pushdowns — constant tension, easy to control, and the cable angle can be adjusted to change the resistance profile
Skull crushers — excellent for loading the triceps through a deep stretch at the bottom of the movement
Overhead cable extensions — places the long head in a stretched position due to shoulder flexion, which may provide additional stimulus

Each variation has slightly different resistance curves. But the common thread is the same: isolated elbow extension that recruits all three heads.

Isolated tricep extensions are the single most effective exercise category for triceps growth because they're the only movements where all three heads can contribute maximally.

Why Pressing Alone Won't Build Complete Triceps

Here's where a lot of "just bench more" bros go wrong.

Compound pressing exercises like bench press, overhead press, and dips do train the triceps. But they don't train ALL of the triceps equally.

The problem is the same biarticular issue we saw with biceps and rows. Just in reverse.

The long head of the triceps performs elbow extension AND shoulder extension.

Pressing movements involve elbow extension (good) and shoulder flexion (the exact opposite of what the long head does at the shoulder).

So during a bench press, the long head is shortening at the elbow but lengthening at the shoulder. Opposing actions. Compromised recruitment.

The lateral and medial heads? They're fine. They only cross the elbow joint, so they contribute fully to the pressing movement without any conflict.

But the long head, which is the largest portion of the triceps, gets shortchanged.

Exercise	Lateral/Medial Heads	Long Head
Tricep extensions	Fully trained	Fully trained
Bench press	Fully trained	Compromised
Overhead press	Fully trained	Compromised
Dips	Fully trained	Compromised

This is why lifters who only do pressing movements often have underdeveloped long heads. The inner portion of their triceps lags behind the outer portion.

If you want complete triceps, you need isolation work. Period.

Pressing exercises can build the lateral and medial heads effectively, but the long head requires dedicated extension work because pressing creates opposing joint actions that limit its recruitment.

The Role of Pullovers in Triceps Development

Pullovers are an interesting case for triceps training.

These exercises involve isolated shoulder extension without any elbow movement. Think cable pullovers or dumbbell pullovers where you keep your arms relatively straight.

Because the long head of the triceps produces shoulder extension, it does contribute to pullover movements.

But here's the catch.

The lateral and medial heads don't cross the shoulder joint. They only extend the elbow. So during a pullover, those two heads sit there doing absolutely nothing.

You're essentially training one-third of the triceps while leaving two-thirds on the bench.

On top of that, the lats and other back muscles are the primary movers during pullovers. The long head of the triceps is a secondary contributor at best.

So are pullovers useless for triceps? Not entirely. They do provide some long head stimulus. But they're nowhere near as efficient as a tricep extension that trains all three heads simultaneously.

Use pullovers for your back. Use extensions for your triceps.

Pullovers can contribute to long head development, but they leave the lateral and medial heads completely untrained. They're a poor substitute for dedicated tricep extension work.

Biceps Technique: Forearm Rotation and Supination

Here's a small technique tweak that can squeeze more growth out of your curls.

Some curl variations lock your forearms into a fixed position. Barbell curls and EZ bar curls, for example. Your grip is set, and your wrists don't rotate.

But with exercises like dumbbell curls, your wrists are free to move.

When you have that freedom, use it.

Start with a neutral grip (palms facing your body) at the bottom of the curl. As you lift, gradually rotate your palms upward so they face your body at the top.

Why does this work?

Because the biceps brachii performs forearm supination. Research confirms that supinated grip positions produce greater biceps brachii activation than neutral or pronated grips. By starting in a slightly pronated or neutral position and actively supinating as you curl, you're adding range of motion to a movement the biceps is designed to do.

You're essentially getting a two-for-one deal: elbow flexion plus supination in a single rep.

It's a small detail. But small details compound over months and years of training.

Quick Checklist for Supinating Curls

Use dumbbells or any implement that allows free wrist rotation
Start with palms in a neutral position at the bottom
Rotate palms to face upward as you curl to the top
Control the reverse rotation on the way down
Don't force excessive rotation. Let it happen naturally

Adding forearm supination during dumbbell curls increases the range of motion for the biceps brachii. Start neutral at the bottom, finish supinated at the top.

Biceps Technique: Shoulder Position During Curls

This is the single biggest technique mistake people make during curls.

And it completely undermines the point of doing them.

When you curl, your shoulder joint should stay relatively fixed. Ideally, no extension should occur at the shoulder during the concentric (lifting) phase.

Here's why.

If you let your elbow drift backward as you curl (which is shoulder extension), you're creating the same opposing-action problem that makes rows suboptimal for biceps.

The biceps brachii is shortening at the elbow but lengthening at the shoulder. Two opposing actions. Reduced stimulus.

This happens more than you'd think. Lifters unconsciously swing their elbows back to generate momentum or make the lift easier. It feels like a stronger curl, but it's actually a weaker biceps stimulus.

What to do instead:

Keep your elbows pinned at your sides or slightly in front of your torso.

If anything, allow a small amount of shoulder flexion at the top of the curl. This means letting the elbows come forward slightly. That actually assists the biceps brachii rather than fighting against it.

Think of it as a spectrum:

Shoulder Movement	Effect on Biceps
Shoulder extension (elbows drift back)	Harmful. Creates opposing actions.
Shoulder stays fixed	Ideal. Clean elbow flexion.
Slight shoulder flexion (elbows come forward)	Beneficial. Assists biceps brachii.

Keep your elbows stationary or allow them to drift slightly forward during curls. Never let them swing backward. Shoulder extension during curls creates the same opposing-action problem that limits biceps growth during rows.

Triceps Technique: Keeping the Shoulder Joint Honest

The same biarticular problem that affects biceps technique also applies to triceps.

Just in the opposite direction.

When performing isolated tricep extensions (skull crushers, cable pushdowns, overhead extensions), you want to avoid any shoulder flexion during the movement.

The long head of the triceps performs shoulder extension and elbow extension. If shoulder flexion creeps into your tricep isolation work, the long head starts fighting itself with opposing joint actions.

This is sneaky. It happens all the time during skull crushers when lifters let their elbows drift backward toward their head. What starts as a pure elbow extension gradually becomes a pressing motion.

More weight? Sure. More tricep stimulus? Probably less.

However, a little bit of shoulder extension during tricep work is actually fine.

For example, during a cable pushdown, if your elbows move slightly forward on the eccentric and then pull back toward your body on the concentric, that's shoulder extension. The long head actually contributes to this movement, so it's not a problem.

The Rule Is Simple

Shoulder flexion during tricep extensions = bad. It creates opposing actions for the long head.
Shoulder extension during tricep extensions = fine. It complements what the long head already does.

Just like with curls, strict form beats heavy form when it comes to arm isolation work.

Avoid shoulder flexion during tricep extensions at all costs. It turns your isolation exercise into a pressing movement and limits long head recruitment. Some shoulder extension, however, is perfectly acceptable.

Putting It All Together: Programming Arms for Growth

Now that you understand the anatomy, exercise selection, and technique considerations, here's how to apply it all within a well-planned mesocycle.

Biceps Programming

Your biceps training should revolve around curl variations. That's the primary movement category.

Don't rely on back exercises to do the work. Rows and pull-ups will train the brachialis decently, but the biceps brachii needs dedicated curl work for maximum development.

A solid approach:

2-4 sets of curls, 2-3 times per week with progressive overload applied over time, following sound overload principles
Include at least one variation that allows supination (like dumbbell curls), and use double progression to systematically add load
Keep elbows fixed or slightly forward during all curl variations
Train through a full range of motion at the elbow joint
Aim for 8-15 reps on most sets. Our rep range calculator can help you find the sweet spot for each exercise.

Triceps Programming

Your triceps training should revolve around isolated elbow extension exercises. Cable pushdowns, skull crushers, and overhead extensions should be the backbone.

Pressing exercises will contribute some stimulus to the lateral and medial heads, but the long head needs extension work.