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The #1 Arm Workout That Blew Up My Arms (4 Exercises)

by Jeremy Ethier - December 2, 2023

Today, we'll use the latest science to create the perfect arm workout that'll blow up your arms.

Thor, Captain America, and Sam Sulek.

What’s the 1 thing they have that every guy wants?

A big… thick… juicy… set of arms. 

Unfortunately, God blessed me with twigs.

So, I spammed them with curls and pushdowns in every single arm workout for bigger arms, but that only worked for so long, and I had no idea that I wasn’t hitting all the arm muscles.

As soon as I trained smarter, my arm growth took off.

I don’t want you to make the same mistakes I did, so today we’ll use the latest science to create the perfect arm workout to blow up your arms. 

There are only 4 exercises, but proper form is crucial, so pay attention if you want to grow your arms. 

Exercise 1: Preacher Curls

The first exercise in our arm workout: let’s start with the biceps.

So, most people’s approach here is to spam their biceps with a bunch of different curls until they can barely raise their arms.

But, guys, efficiency is everything.

We can get a lot more growth by picking the right exercises and doing them well.

To find the best options, let’s take a look at some recent research. 

So the thing about a standing dumbbell curl is it’s hardest in the middle right around here. 

Make Use Of "Stretch-Mediated Growth" In Your Arm Workout

But a new area of research suggests that for the most growth, you’d want an exercise that challenges the biceps the most closer to the bottom when the bicep is fully stretched

Illustrating the effectiveness of this is a 2023 study that had subjects do either incline curls or preacher curls over the course of 9 weeks. FYI:

  • Incline curls: Challenge the biceps the most in the middle.
  • Preacher curls: Challenge the biceps closer to the beginning, when the bicep is almost fully stretched.

So, what ended up working better?

Well, the preacher curls led to more growth at all 3 measurement sites of the biceps, especially in the bottom part of the biceps.

There have been similar findings in other muscles like the hamstrings, quads, and as you’ll see later on the triceps as well.

This makes me relatively confident in selecting preacher curls as a “top tier” biceps exercise for our arm workout, especially since our Built With Science program members have also seen a lot of success with them.

How To Perform Preacher Curls For More Growth

But there’s a way to perform them if you wanna get even more growth from your arm workout.

First off, the biceps function to not only flex the arm but also turn the wrists inwards. So to potentially get even more growth, try to start the curl with a neutral grip and then turn your wrists in so your palms face up at the top.

However, this will reduce the range of motion if you’re using an incline bench, so I’d only recommend doing it if you’re using an actual preacher curl bench. 

How to perform preacher curls in an arm workout for more growth

Second, given the importance of the stretch, your arm should be almost fully extended at the bottom. But this is usually a position that most people have never trained their biceps in.

How to perform preacher curls in arm workout for more growth 2

So I’d recommend starting off with lighter weight for 10-20 reps, and then over time, you can go relatively heavier for around 8-12 reps. 

Exercise 2: Hammer Preacher Curls

Alright, so there’s 1 more curl we’ll want to do in our arm workout to really blow up the arms.

This one will help grow not just your biceps, but 2 more arm muscles:

  1. Brachioradialis: The biggest muscle of the forearm
  2. Brachialis: A muscle between the biceps and triceps that can help thicken your arms

Now, unfortunately, there’s no direct evidence looking at how well different exercises grow these muscles.

But the brachioradialis sits on the side of the forearm.

So simply turning your grip to neutral will line it up better with the direction of the arm path during the curl, forcing it to do more work.

This grip is also theorized to reduce the involvement of the biceps and increase that of the brachialis.

Now, standing hammer curls are the usual go-to for these muscles.

But for an even greater benefit, we can apply the earlier research we went through and perform these on a preacher curl to make it difficult at the beginning of the exercise, when the muscles are more stretched. 

Use a bench for hammer curls in arm workout for more growth

Similar to the regular preacher curl, start off lighter for higher reps and work your way to 8-12 reps with a relatively heavier weight.

But if these feel tough on your tendons, feel free to stick with lighter weights and higher reps or swap them for behind-the-body hammer cable curls in your arm workout, which will still challenge the muscles more when they’re stretched. 

Behind the body hammer cable curls in arm workout

Exercise 3: Overhead Extensions

Now, time to target the triceps in our arm workout.

There are 3 heads in the triceps:

  1. Medial head
  2. Lateral head
  3. Long head

Some of these heads already grow very well indirectly from other exercises you’re already doing.

One study published back in 2020 found that the bench press grew the lateral and medial heads quite well. But led to virtually no growth in the biggest head of the triceps, the long head.

This is because the long head is unique in that it’s the only head that crosses the shoulder joint. 

So you’ll need a special exercise to target it.

As for the best option to include in your arm workout, the study we just covered also tested what would happen if subjects did both the bench press and skullcrushers, a common triceps exercise.

Compared to doing just the bench press alone, adding the skullcrushers resulted in no additional growth in the lateral head and a bit of growth in the medial head, but considerably more growth in the long head. 

But what exactly makes skullcrushers so effective?

And what about other tricep exercises? Would they be just as good at growing the long head?

A Good Skullcrushers Alternative To Include In Your Arm Workout

Well, another recent study by Maeo and colleagues provides some insight.

They had subjects do tricep overhead extensions with one arm and tricep pushdowns with the other.

Similar to skullcrushers, overhead extensions place the long head in a greater stretch, which as we know from other research, seems to provide better gains. 

The result?

After 12 weeks, the overhead extension group experienced about 1.5 times the growth in the long head! 

What’s interesting is that even though the lateral and medial heads weren’t stretched anymore during the overhead extension, they still grew significantly more.

We definitely need more research to find out why, but I would be pretty confident in recommending some type of overhead extension as a top-tier triceps exercise to include in your arm workout — at least for the long head.

Cable overhead extensions in arm workout

But choose whatever is comfiest on your joints:

  • Overhead with a rope or
  • Single arm with just the cable or
  • Skullcrushers using dumbbells or barbells

Aim for about 10-15 reps on these using moderate weight. 

Don't Neglect These

Guys, before I show the last exercise in the arm workout, I need to be honest with you.

While all this science can definitely give you an edge, you're not going to get big arms if you’re not nailing down the foundation — no matter how hard you're training.

You need to:

You’ll get far better results by fixing those areas than you will with any workout, no matter how “science-based” it is.

If you’re someone who needs more guidance and wants a step-by-step science-based training and nutrition plan that takes care of all the guesswork for you so you can build muscle and lose fat as efficiently as possible, just take our quiz below to find the best plan for you and your body. It's helped thousands of others, and I guarantee it'll work for you.

Click the button below to take my analysis quiz to discover the best program for you:

Exercise 4: Lateral Head Extensions

Alright, we’ve covered the long head, but now, let’s target the 2 other tricep heads in our arm workout.

You’ve already learned that pressing movements alone do a good job of growing the lateral and medial heads.

For some people, that may be all you need.

But my pressing has always been relatively weak, and my lateral head seemed to lag behind.

So adding an exercise dedicated to this area to my arm workout really helped out. 

As for the best option, I’ve found a lot of success with an exercise I first learned from biomechanics expert Coach Kassem.

The arm position seems to both stretch and challenge the lateral head more when it’s stretched, which as we covered is probably beneficial for growth. 

To perform it, grab the cable with one hand, face away, and let the cable come over your opposite shoulder. Position your arm in front and across your body, and then simply extend your arm while keeping your elbow locked in place.

Lateral head extensions in arm workout

Aim for about 10-15 reps per set. 

Don't Have Access To Cables?

Now if you don’t have access to cables, another option is close grip push-ups or something called the JM press but with dumbbells. 

You can think of the exercise as if skullcrushers and close grip dumbbell press had a baby. 

It’ll help emphasize the lateral and medial heads since as we saw earlier, the long head doesn’t do a very good job at helping out during pressing-type exercises.

To perform it, lower the dumbbells down towards your neck while sliding your elbows forward.

JM press as an alternative in your arm workout

You want as much elbow bend as possible, such that your forearm is parallel with the ground at the bottom. You can let them angle out on the way down if it’s more comfy on your elbows.

How to perform the JM press in your arm workout

Then, simply use your triceps to extend your arms back up. 

However, for some people, these can be tough on the elbows, so I’d recommend sticking with lighter weights and aiming for about 15-20 controlled reps. 


  • Preacher curls challenge the biceps closer to the bottom, where they’re fully stretched. Start the curl with a neutral grip, then turn your wrists in for more growth.
  • Hammer curls help grow the biceps, brachioradialis, and brachialis. Perform them on a preacher machine for more stretch and, in turn, more growth.
  • Skullcrushers and overhead extensions work great at targeting the long head of the triceps as they place them in a greater stretch.
  • Include lateral head extensions in your arm workout if the lateral head of your triceps lags in growth. Alternative exercise: close-grip push-ups or JM press.

The #1 Arm Workout

So here are the 4 exercises you should include in your arm workout to absolutely blow up your arms — complete with the reps, sets, and alternatives.

Complete arm workout routine

You can throw these exercises into a few of your workouts throughout the week or have a dedicated arm workout day where you do these all at once.

I’ve been experimenting and found success with both, but it depends on your volume and how much you want to prioritize your arms.

I’ll create a future article that explains this more in-depth. 

But guys the best complement to bigger arms is wider, fuller shoulders. So, I highly recommend checking this article out next if you want to learn about a shoulder workout I’ve been doing that’s been working really well for me.

Thanks for sticking to the end, and I’ll see ya next time!

By the way, here’s the article summed up into a YouTube video:

The #1 Workout That BLEW UP My Arms (4 Exercises)

The #1 Arm Workout That Blew Up My Arms (4 Exercises)