Lying tricep extension extension

How to Do a Lying Tricep Extension With Dumbbell, Barbell, and Cable

The Lying Tricep Extension is a fun, strength-building exercise that goes by quite a few names.

It can also be called the French Extension or French Press. The most dramatic yet aptly titled is the “Skull Crusher”. 

Intimidated? Don’t be! 

This article will cover everything you need to know and more to properly practice this exercise.

The great thing about this effective move is that there are many variations for every fitness level.

It is important to find one that works best for you personally.

This exercise can be completed with a barbell or dumbbells.

Adding weight is useful for building mass or increasing the number of calories burned.

The skull crusher can be performed on a weight bench or a cable machine. Both options are covered below.

So let’s get into it, fitness enthusiasts! 

We will cover how your triceps work, what the muscles are used for, 3 popular variations, mistakes to avoid, and alternatives you can add to your workout!

Also, check out: 30-Day Arm Challenge: Arm Workout to Sculpt Your Best Arms Ever

How Do Triceps Work?

Lying Tricep Extension

Before we learn how the triceps work, where exactly are they located?

The short answer is that your triceps are the muscles along the back of your arms. 

The long answer is that the muscle originates below the scapula (your shoulder blades) socket and 2 areas of the humerus.

Your humerus is your upper arm bone. There are 3 different heads, the long head, the medial head, and the lateral head. 

The muscle extends down and attaches to your ulna, which is located in your forearm. 

So how does it work? Your triceps extend your forearm from the elbow joint. Your biceps, located laterally from the triceps, work in opposition.

Think of the extension and flexion in bicep curls. When one muscle extends, the other relaxes.

To put it plainly, your biceps are the flexors and your triceps are the extenders. 

Check it out in your own body! Lift your right arm overhead as if going into an overhead extension.

Wrap your left fingers around your arm. Specifically, have your thumb on the back of your arm, the other 4 on the top of the arm. 

Bend and straighten your arm, moving through the full range of motion. You can feel your muscles hard at work, switching from extension and flexion. Cool, right?

What Is the Tricep Muscle Used For?

Tricep Muscle Used

As we’ve covered above, the triceps muscle extends the forearm. It also stabilizes the shoulder.

In the shoulder joint, it holds the head of the humerus (your upper arm bone) in the correct position.

The heads of the triceps each have their own duties. The lateral head is activated in movements requiring high-intensity force.

The medial head is used for low force, precise movements (1).

According to, the shoulder needs to be externally rotated for the long head to assist in shoulder adduction (2).

Each head also has a different pattern during various shoulder elevations.

For example, the long head contributes more at shoulder elevation while the medial head kicks in when the shoulder is elevated over 90 degrees (3).

3 Lying Triceps Extensions

There are 3 variations of the basic lying tricep extension utilizing different pieces of equipment all on a flat bench.

For the more advanced, you can use an inclined or declined bench, however, master the flat bench first.

Start with 10 – 15 reps for 2 – 3 sets.

Dumbbell Lying Triceps Extension

Dumbbell lying tricep extension
  • Grab a pair of dumbbells of the weight of your choice and fitness level.
  • Lie on a flat bench, face-up with a dumbbell in each hand. Extend your arms over your chest, directly over the shoulders.
  • Bend at the elbows as you inhale, lowering the dumbbells until they are above your shoulders.
  • Pause for 1 second. Exhale and squeeze your triceps, returning to the starting position. 

Barbell Lying Triceps Extension

Similar to the dumbbell tricep extension, the movement can be completed with a barbell. 

  • Again, lie on a flat bench, face-up. Using a narrow overhand grip on the barbell, extend your arms. The barbell should be over your forehead. 
  • Inhale as you lower the bar, bending at the elbow until the bar goes slightly over your head.
  • On your exhale, extend your arms by flexing your triceps. Don’t lock your elbows.

It’s a good idea to keep a spotter on hand!

Cable Lying Triceps Extension 

  • Set up your weight bench in front of a low pulley using the straight bar attachment, head closest to the handles. Hold the attachment, palms facing forward. 
  • Extend your arms. Slowly lower the weight back with your forearms on an inhale. The bar will rest just above the forehead. 

Engage your triceps as you reextend your arms back to the starting position on an exhale.

Common Mistakes to Avoid

Lying tricep extension mistakes

Loose Grip

First off, make sure you keep a firm grip on your free weights. You don’t want to drop the weight on your face or head.

It’s called a “skull crusher” for a reason. Jokes aside, keep this in mind whenever using weights near or around your head for any exercise.

Lowering Weight Too Close to Your Face

Keeping the focus on your head, do not lower toward your face.

The weight should smoothly travel behind your head. Conversely, be careful not to hit the back of your head when returning to the starting position. 

Unstable Elbows

Next, pay attention to your elbows. They should stay close to the body to engage the targeted muscles.

Moving the Weight too Fast

As with any workout, take your time. Exercise professionals will tell you, proper form is imperative to any great exercise.

Keep control throughout the entire tricep extension. If at any point, you start to lose control or form, stop immediately.

If you’re using additional weight, consider lowering the total load to something more manageable. Again, have a spotter on hand to assist.

Too Much Weight

Lastly, for the best results, this triceps workout should be done with a lower weight and more repetitions, especially if you’re a beginner.

You want to avoid stress in the elbows while keeping proper form and control. If you’re interested in building mass, start low and work up to the heavier weight.

Avoid this workout if you’ve had an elbow injury or pain. Same with your wrists.

If in pain, seek a qualified healthcare professional or medical group from certifying organizations for approval or adjustments.

See below for alternative exercises you can try instead! 

Other effective tricep exercises

Tricep Kickback 

Diamond pushups 

  • Start in a standard plank position with your spine straight, core muscles engaged. There should be a straight line from the tip of your head to your heels.
  • Create a diamond shape with your hands. Your thumbs and index fingers will be touching. This is similar to the narrow grip.
  • Lower your chest to roughly 6 inches from the floor. Your elbows should be pointing back towards your feet, not out to the sides. 
  • Press back up to the starting position. 

Close-Grip Bench Press

  • Lie face-up on a weight bench holding the barbell with a close grip, hands roughly shoulder-width apart. Consider a spotter for safety, especially if you’re lifting heavier weight loads.
  • Inhale as you slowly bring the bar down towards your chest, keeping your elbows in.
  • Exhale and push the bar back up using your tricep muscles. That is 1 bench press or rep.

Triceps Bench Dips

  • Sitting on the edge of a chair or flat bench, grip the edge of the seat by your hips, fingers pointed towards your feet.
  • Keep your feet hip-width distance. You have 2 options with your legs. You can either keep them bent at 90 degrees or extend your legs in front of you. Chin stays up.
  • Press through your hands and lift your body, sliding forward enough that your glutes are no longer on the bench or seat.
  • Lower your glutes until your elbows are between a 45 to a 90-degree angle. Press back up to the starting position. 

Overhead Triceps Extension

The overhead triceps extension is an exercise that can be completed either seated or standing. When sitting, it’s known as a seated tricep press. (

  • Grip a dumbbell, medicine ball, or kettlebell firmly in both hands overhead, arms extended. 
  • With an upright torso on an inhale, lower the weight behind your head toward your shoulder blades, keeping your biceps close to your ears. 
  • Exhale, returning back to the starting position.

Tricep Kickback 

As a personal trainer, the tricep kickback is one of my favorite upper body exercises. It is also a great exercise to target the long head of the triceps. 

This can be completed as a bodyweight exercise until the proper form is mastered. 

  • Once comfortable with the movement, hold a dumbbell in each hand, palms facing in.
  • With a slight bend your knees, engage your abs and hinge forward at the hips. Lower your torso until it is almost parallel to the ground. 
  • Your upper arms stay close to your body as you engage your triceps and straighten your arms behind you. Only move your forearms. Pause and return. 

You can also work one arm at a time. Make sure you complete the same number of reps on each side. 

If you need additional back support, try this movement on a flat bench.

Have your right shin resting on the bench, the left leg extended, foot firmly planted into the ground.

Your right hand is on the bench, directly under your shoulder. Perform the kickback with your left arm. Repeat on the opposite side. 

The Takeaway on Lying Tricep Extension

Your tricep is in the muscle group located at the back of your upper arm and is responsible for the extension of the arm, among other things listed above.

You have 3 tricep heads, each with their own duties as well. 

There are many variations of the lying tricep extension aka skull crushers, 3 were covered here as well as many other options such as the overhead triceps extension or tricep kickbacks. 

Add one of these to your workout or superset today! 

Note that these exercises are for educational purposes. Seek medical advice from a qualified healthcare provider or a c.s.c.s. prior to starting any new workout plan.


  1. Https://
  2. “Triceps Brachii.” Physiopedia,
  3. Triceps,

About the Author

Similar Posts