How to Build Triceps Without Wrecking Your Elbows

Let’s talk about the most brutally named exercise in the gym: skull crushers. Sounds like something a WWE wrestler would do to their nemesis, right? But in reality, it’s one of the best moves for carving triceps that look like horseshoes and bench-pressing like a beast. The catch? Most people butcher this exercise so badly that they end up with elbow pain, shoulder tweaks, and zero gains.

As a trainer who’s rehabbed more creaky elbows than I can count (thanks, ego lifters!), I’m here to break down how to do skull crushers right. Spoiler: If your elbows flare like chicken wings, you’re doing it wrong. Let’s fix that.

Skull crushers (aka lying triceps extensions) are an isolation exercise targeting the triceps — specifically the long head, which gives your upper arm that full, defined look.

They involve lowering a weight toward your forehead or behind your head while lying on a bench, keeping your elbows locked in place. Think of it like a reverse bicep curl but for the back of your arms.

Primary Muscle Worked:

Triceps Brachii

• Long head
• Lateral head
• Medial head

The triceps brachii is the star of this move. Skull crushers hit all three heads, making them one of the best triceps exercises for overall mass and definition.

Secondary Muscles Engaged:

1. Forearms (Anconeus & Wrist Stabilizers)

These small muscles help stabilize the elbow joint and wrist during the lowering and pushing phase.

2. Shoulders (Deltoids – anterior)

Not heavily involved, but they stabilize your upper arm to keep it in place during the lift.

3. Core (Stabilizers)

Especially in lying or incline variations, your core engages to maintain posture and support your spine.

Let’s break it down:

✅ Pure Isolation – Skull crushers isolate your triceps better than most compound lifts.

✅ Crazy Versatility – Use dumbbells, barbells, resistance bands, or a cable machine.

✅ Improves Lockout Strength – Great for boosting your performance in bench presses and dips.

✅ Beginner-Friendly Setup – Simple movement, easy to learn, and adjustable to any fitness level.

• Lie flat on a bench, feet planted.
• Grab an EZ-bar, dumbbells, or a barbell. Start light (10-20 lbs for beginners).
• Press the weight straight up, arms perpendicular to the floor.

• Bend your elbows to lower the weight toward your forehead (not behind your head!).
• Keep your elbows tucked at 45 degrees—no flaring!
• Stop when your forearms are parallel to the floor.

• Drive the weight back up by extending your elbows.
• Squeeze your triceps at the top. No half-reps!

Pro Tip: Imagine you’re hinging at the elbows, not the shoulders. Your upper arms should stay fixed.

These are great if you’re starting or returning from a break.

What it is: A bodyweight version performed using a fixed bar or Smith machine.

How to do it: Set the bar at about waist height. Stand behind it, grip shoulder-width apart, and lower your forehead toward the bar by bending your elbows.

Why it’s great: No weights required, you’ll build control, elbow stability, and foundational tricep strength.

What it is: The classic version done lying on a bench with two dumbbells.

How to do it: Lie back on a flat bench, hold a dumbbell in each hand, and bend your elbows to lower the weights near your ears.

Why it’s great: Dumbbells offer independent arm movement, perfect for correcting strength imbalances.

These help improve muscle engagement, time under tension, and range of motion.

What it is: A step up from dumbbells, using a curl EZ bar for wrist comfort and greater loading.

How to do it: Lie on a bench, grip the EZ bar with a narrow grip, and lower it behind your head in a controlled arc.

Why it’s great: Allows you to increase weight while maintaining better wrist ergonomics.

What it is: Performed on an incline bench to increase stretch on the long head of the triceps.

How to do it: Set the bench at a 30-45° incline, perform skull crushers as usual.

Why it’s great: Greater stretch = greater muscle fiber recruitment and long head focus.

What it is: Uses the cable machine with a rope attachment to provide continuous tension.

How to do it: Set the rope at a high pulley, kneel or sit, and pull the rope toward your forehead.

Why it’s great: Less stress on joints, more constant tension on the triceps.

For those who want to level up their intensity and hypertrophy.

What it is: Combines a close-grip bench press with a skull crusher.

How to do it: Lower the bar down toward your upper chest with elbows tucked, press up with triceps.

Why it’s great: Builds lockout strength and triceps mass—perfect for lifters and power athletes

What it is: Adds accommodating resistance via bands or chains.

How to do it: Perform barbell skull crushers while bands pull the bar up or chains load more at the top.

Why it’s great: Makes the lockout harder and keeps constant resistance. Encourages explosive strength.

What it is: A skull crusher variation performed on a decline bench.

How to do it: Lie on a decline bench and perform skull crushers as normal.

Why it’s great: Targets the long head even more by increasing shoulder flexion.

Even the most well-intentioned gym-goers can fall prey to skull crusher mistakes. Let’s identify these pitfalls and learn how to sidestep them:

1. The Flaring Elbows: Keep your elbows tucked in and pointing forward, not flaring out to the sides like a bird trying to take flight.
2. The Moving Upper Arms: Your upper arms should stay stationary throughout the movement. If they’re rocking back and forth, you’re turning your skull crushers into a weird hybrid exercise.
3. The Speed Demon: Slow and controlled beats fast and reckless every time. This isn’t a race – it’s precision tricep sculpting.
4. The Ego Lifter: Don’t let your ego choose the weight. Start lighter than you think you need and focus on perfect form.
5. The Range of Motion Cheater: Going through the full range of motion is crucial. Don’t shortchange yourself with partial reps.

• Sharp elbow pain: You’re overextending or using too much weight. Deload and check the form.
• Achy shoulders: You’re lowering the weight too far back. Shorten the range of motion.
• Wrist discomfort: Switch to an EZ-bar or dumbbells for a neutral grip.

Still hurt? Try these elbow-friendly alternatives:

• Tricep pushdowns (with a rope or V-bar).
• Close-grip bench press.
• Overhead dumbbell extensions.

Absolutely. Here’s what you can use:

• Dumbbells or resistance bands
• A bench, a stability ball, or just the floor
• A backpack filled with books (yes, we’ve all done it)

Pro tip: If you don’t have weights, resistance bands give great time-under-tension.

Here’s a quick guide based on your goals:

Use moderate weight and go slow on the eccentric (lowering) phase. That’s where the magic happens.

• Dips hit all heads, but are compound and bodyweight.
• Skull crushers isolate the long head more.

Close-Grip Bench Press

• Great for adding overall strength.
• Less isolation, more chest involvement.

Overhead Triceps Extensions

• Also great for long head, but harder to control from.
• Use both for well-rounded arms.

If you’ve been skipping skull crushers, your triceps are missing out. This move may look simple, but it packs a punch. Add them to your routine consistently, play with the variations, and watch your arms transform.

So go ahead — crush it (safely, of course).