Introduction
Well-developed triceps are essential for building stronger arms and improving pressing strength in exercises such as the bench press and overhead press. Because the triceps make up roughly two-thirds of the upper arm, focusing on effective triceps isolation movements can significantly improve overall arm size and strength.
One of the most popular exercises for targeting the triceps is the EZ-bar skull crusher, also known as the lying triceps extension. This exercise allows lifters to apply significant tension to the triceps while keeping the movement focused almost entirely on elbow extension.
Other Names for the EZ-Bar Skull Crusher
This exercise is known under several different names depending on the training community, coaching style, or equipment used. Understanding these alternative names can help you recognize the movement across different workout programs and fitness resources.
- EZ-bar skull crushers
- Skull crushers
- EZ-bar lying triceps extension
- Lying triceps extension
- Lying EZ-bar extension
- EZ-bar triceps extension
The exercise earned the nickname “skull crushers” because the bar is lowered very close to the forehead during each repetition. That dramatic bar path gave the movement its memorable name, but it also serves as a reminder that skull crushers should always be performed with strict control, proper setup, and respect for the weight.
Required Equipment
The EZ-bar skull crusher requires only a few pieces of standard gym equipment, making it accessible in most commercial gyms and home training setups.
- EZ curl bar – reduces wrist strain compared with a straight bar
- Flat bench – provides a stable base for performing the exercise
- Weight plates – used to adjust resistance
- Optional spotter – helpful when lifting heavier loads
How to Perform the EZ-Bar Skull Crusher
Proper setup is essential for performing skull crushers safely and effectively. Because the bar travels close to the head during the movement, maintaining good control and stable arm positioning is extremely important.
Starting Position (Setup)
- Lie flat on a bench with your head, back, and glutes in contact with the bench.
- Keep your feet flat on the floor for stability.
- Hold an EZ-bar with a narrow overhand grip.
- Extend the bar above your chest with arms straight but angled slightly back toward your head rather than perfectly vertical.
- Keep your upper arms relatively stationary throughout the lift.
Movement (Execution)
- Slowly bend your elbows to lower the bar toward your forehead or slightly behind your head.
- Keep your upper arms stable and elbows pointing upward throughout the movement.
- Pause briefly near the bottom of the repetition.
- Extend your elbows to press the bar back to the starting position.
- Maintain control during both the lowering and lifting phases.
Video Demonstration
Watching a proper demonstration of the EZ-bar skull crusher can help you better understand the correct bar path, elbow positioning, and tempo of the movement. Observing the exercise performed with strict form is often the easiest way to learn how to keep the upper arms stable while focusing the effort on the triceps.
Below, you can watch a video demonstration that shows the correct technique for performing EZ-bar skull crushers safely and effectively.
When watching the demonstration, pay close attention to how the upper arms remain relatively stationary while the forearms move through the range of motion. This is the key technical detail of the skull crusher — the movement should occur almost entirely at the elbow joint, with minimal shoulder involvement. Keeping the elbows stable helps maximize triceps tension and prevents the chest or shoulders from assisting the lift.
Muscles Worked in EZ-Bar Skull Crushers
The EZ-bar skull crusher primarily targets the muscles responsible for elbow extension. Because the upper arms remain relatively stationary during the movement, the triceps perform most of the work while several stabilizing muscles assist in maintaining joint control.
- Primary muscles: triceps brachii (long head, lateral head, medial head)
- Secondary muscles: anconeus
- Stabilizing muscles: posterior deltoids, upper back stabilizers
- Antagonist muscles: biceps brachii, brachialis, brachioradialis
Biomechanics of the EZ-Bar Skull Crusher
Understanding the biomechanics of the skull crusher helps explain why the exercise can be extremely effective for triceps development. The movement is based on controlled elbow extension, with the upper arm remaining mostly fixed relative to the torso.
During the lowering phase, the elbows flex and the triceps lengthen under tension. When the weight is extended back to the starting position, the triceps contract to straighten the elbows. This repeated elbow extension creates significant mechanical tension in the triceps, especially when the bar is lowered slightly behind the head, which increases the stretch on the long head of the triceps.
Technique Optimization Tips
Small adjustments in technique can significantly improve both the safety and effectiveness of skull crushers. Paying attention to elbow positioning and movement control helps maintain constant tension on the triceps.
- Keep your upper arms relatively stationary throughout the movement.
- Lower the bar slowly and under control, especially near the bottom.
- Maintain a firm wrist position to prevent unnecessary joint strain.
- Keep the elbows slightly tucked inward rather than flaring outward.
- Avoid using excessive weight that forces you to involve the shoulders.
Quick Form Checklist
When performing skull crushers, a quick mental checklist can help ensure proper technique. Running through these cues before each set can greatly improve exercise execution.
- Upper arms are stable and angled slightly back
- Elbows pointing upward and not drifting outward
- Controlled lowering of the bar
- Bar path directed toward the forehead or slightly behind the head
- Smooth elbow extension during the lifting phase
In my coaching experience, there is probably no exercise for any body part that has gained such a reputation for causing elbow discomfort as skull crushers. Even when lifters use an EZ-bar — which is usually recommended to reduce wrist strain — some people still experience irritation in the elbows or wrists. If this happens to you, one solution I often suggest is switching to dumbbell lying triceps extensions. Using dumbbells allows a neutral (hammer-style) grip, which usually places the wrists in a more comfortable position and often reduces stress on the elbow joint. Many lifters immediately notice that the movement feels smoother and more natural compared with using a barbell.
Technical Emphasis & Targeting Adjustments
Minor adjustments to arm position and bar path can change how the triceps are loaded during skull crushers. These variations allow lifters to emphasize different portions of the triceps depending on training goals.
- Lowering the bar slightly behind the head increases stretch on the long head of the triceps.
- Keeping the bar directly above the forehead often makes the movement slightly easier and more controlled.
- Using a slightly narrower grip can increase triceps isolation.
- Using an EZ-bar rather than a straight bar often improves wrist comfort and reduces joint stress.
Common Mistakes
Although the EZ-bar skull crusher is a relatively simple exercise, several common technique errors can reduce its effectiveness or increase stress on the joints. Paying attention to proper elbow positioning and movement control will help ensure the triceps perform the majority of the work.
- Allowing the elbows to flare outward.
When the elbows move too far apart, the shoulders and chest begin assisting the lift. Keeping the elbows slightly tucked helps maintain proper triceps isolation. - Using excessive weight.
Many lifters attempt to lift too heavy during skull crushers, which often leads to poor control and unstable elbow positioning. Using a manageable weight allows better tension on the triceps. - Lowering the bar too quickly.
Dropping the bar toward the head without control reduces time under tension and increases the risk of injury. The lowering phase should always be slow and controlled. - Moving the upper arms during the lift.
If the upper arms drift forward or backward, the shoulders begin to assist the movement. Ideally, the upper arms should remain relatively stationary throughout the entire repetition. - Extending the shoulders instead of the elbows.
Some lifters unintentionally turn the movement into a hybrid pullover by moving their arms backward. Skull crushers should primarily involve elbow extension rather than shoulder movement. - Locking the elbows too aggressively at the top.
Snapping the elbows into full lockout can place unnecessary stress on the elbow joints. A controlled extension with slight tension maintained is usually safer and more effective.
EZ-Bar Skull Crushers Pros and Cons
Like most isolation exercises, skull crushers offer several important advantages for triceps development, but they also have a few limitations that lifters should understand. Knowing both the benefits and potential drawbacks helps you decide how and when to include this exercise in your training routine.
Benefits
- Excellent triceps isolation. Because the movement focuses on elbow extension while the upper arms remain relatively stationary, the triceps perform most of the work during the exercise.
- Strong hypertrophy stimulus. Skull crushers allow lifters to apply significant mechanical tension to the triceps, making them highly effective for building muscle size.
- EZ-bar improves wrist comfort. The angled grips of the EZ bar place the wrists in a more natural position compared with a straight bar, which often reduces wrist strain.
- Easy to progressively overload. Since the exercise uses a barbell, increasing the training load over time is simple and effective for progressing strength and hypertrophy.
Downsides
- Potential elbow discomfort. Some lifters experience elbow irritation when performing skull crushers, especially if the weight is too heavy or the elbows flare outward.
- Requires strict control. Because the bar travels close to the head, poor control or excessive weight can increase the risk of injury.
- Limited stabilization training. Compared with some free-weight movements performed standing, skull crushers involve less overall body stabilization.
EZ-Bar Skull Crushers Variations
Although the EZ-bar skull crusher is the most common version of this exercise, several variations can slightly modify the training stimulus. These alternatives can help reduce joint stress, emphasize different parts of the triceps, or simply add variety to your arm workouts.
Straight Bar Skull Crushers
This variation is performed with a standard straight barbell rather than an EZ bar. While the movement mechanics remain almost identical, the straight bar places the wrists in a fully pronated position, which some lifters may find less comfortable.
Dumbbell Lying Triceps Extension
This variation uses a pair of dumbbells instead of a barbell. Because each arm moves independently, dumbbells can improve muscular balance and often place less stress on the wrists and elbows.
Wide-Grip Skull Crusher
Using a wider grip on the EZ bar slightly changes the mechanics of the movement. Some lifters find that this grip increases activation of the long head of the triceps, although the difference is usually subtle.
Reverse-Grip Skull Crusher
Performing the exercise with a supinated (reverse) grip shifts the emphasis slightly toward the medial and lateral heads of the triceps. However, this grip can feel less stable and should typically be performed with lighter weights.
Cable Lying Triceps Extension
In this variation, a bench is placed near a low pulley cable machine, and the movement is performed using a cable attachment. Cable resistance provides more consistent tension throughout the range of motion compared with free weights.
Neutral-Grip Triceps Bar Extension
Some gyms provide a specialized triceps bar with parallel handles. This neutral grip often feels more comfortable for lifters who experience wrist or elbow discomfort during traditional skull crushers.
Replacement Exercises (Substitutes)
If skull crushers do not feel comfortable, or if you simply want more variety in your triceps training, several other exercises can effectively target the same muscle group. Each alternative places slightly different mechanical stress on the triceps.
- Seated dumbbell triceps extension
- Resistance band-assisted triceps dips
- Incline EZ bar lying triceps extension
- Cable lying triceps extension
- Lying dumbbell triceps extension
- Cable overhead triceps extension
- Seated EZ bar overhead triceps extension
- Machine dips
- Parallel bar dips
These exercises can be used interchangeably within a training program depending on equipment availability, training goals, and individual joint comfort.
Where This Exercise Fits in a Workout
The EZ-bar skull crusher can be incorporated into different parts of a triceps workout, depending on the training goal and overall program structure. Because the exercise isolates the triceps and limits assistance from other muscle groups, it is most commonly performed after compound pressing movements.
In many programs, skull crushers are used after exercises such as the bench press, close-grip bench press, or dips. Once the larger compound lifts are completed, skull crushers allow the lifter to further fatigue the triceps with controlled isolation work.
Some lifters also use skull crushers as a primary triceps movement when the goal is to maximize elbow extension strength and triceps hypertrophy. In this case, the exercise may be placed earlier in the workout while the muscles are still relatively fresh.
Sets and Reps Recommendation
Choosing the right set and repetition scheme depends on whether the goal is muscle growth, strength development, or muscular endurance. Because skull crushers place significant stress on the elbows, moderate rep ranges usually work best.
- Muscle hypertrophy:
3–4 sets of 8–12 repetitions - Strength emphasis:
4–5 sets of 5–8 repetitions - Muscular endurance/pump work:
2–3 sets of 12–15 repetitions
In most bodybuilding-style training programs, the 8–12-rep range is considered ideal because it allows sufficient load while maintaining safe control of the bar path near the head.
EZ-Bar Skull Crushers vs. Close-Grip Bench Press
Both skull crushers and the close-grip bench press are excellent triceps exercises, but they train the muscles in slightly different ways. Understanding these differences can help lifters choose the right exercise for their training goals.
| Training Factor | EZ-Bar Skull Crushers | Close-Grip Bench Press |
|---|---|---|
| Exercise Type | Isolation | Compound |
| Primary Movement | Elbow extension | Elbow extension + shoulder flexion |
| Muscles Emphasized | Triceps brachii | Triceps, chest, anterior deltoids |
| Stability Requirement | Moderate | Higher full-body stabilization |
| Load Potential | Moderate | High |
| Best Use | Triceps isolation & hypertrophy | Strength and compound pressing power |
Conclusion: Both exercises can be valuable in a triceps training program. The close-grip bench press allows heavier loading and recruits additional muscle groups, while skull crushers provide more direct isolation of the triceps. Many lifters include both exercises in their workouts to combine heavy compound strength with targeted arm development.
Final Thoughts
The EZ-bar skull crusher remains one of the most recognizable and widely used triceps exercises in strength training. When performed with proper technique and controlled tempo, it can provide a powerful stimulus for triceps hypertrophy and elbow extension strength.
Because the movement isolates the triceps so effectively, it works particularly well when combined with compound pressing exercises such as the bench press or dips. Using moderate weights and maintaining strict elbow positioning will help maximize muscle tension while reducing unnecessary stress on the joints.
For lifters looking to build stronger, more developed arms, the EZ-bar skull crusher remains a valuable addition to a well-structured upper-body training program.
Why are skull crushers sometimes called lying triceps extensions?
The two names refer to the same basic movement pattern. “Lying triceps extension” is the technical description of the exercise, while “skull crushers” is a gym nickname that became popular because the bar travels very close to the head during each repetition.
Should the bar touch your forehead during skull crushers?
Not necessarily. Many experienced lifters actually lower the bar slightly behind the head rather than directly to the forehead. This increases the stretch on the long head of the triceps and often feels more comfortable on the elbows.
Are skull crushers safe to perform without a spotter?
Yes, but only if the weight is manageable and the lifter maintains strict control of the bar. When using heavier loads, a spotter can help rerack the bar safely at the end of a set, especially when fatigue sets in.
What grip width works best for EZ-bar skull crushers?
A shoulder-width or slightly narrower grip usually works best for most lifters. Extremely narrow grips can strain the wrists, while very wide grips may reduce triceps isolation.
Why do some lifters feel skull crushers more in their shoulders?
This usually happens when the upper arms move excessively during the lift. If the shoulders begin to assist the movement, the exercise becomes less of a pure triceps isolation movement.
Can skull crushers be performed on an incline bench?
Yes. Performing skull crushers on a slight incline changes the angle of resistance and can increase the stretch on the triceps. Some lifters find this variation more comfortable for the elbows.
Should skull crushers be performed slowly or explosively?
Most coaches recommend a controlled tempo, particularly during the lowering phase. A slow eccentric phase increases time under tension and reduces the risk of losing control of the bar near the head.
Can beginners perform skull crushers safely?
Yes, beginners can perform skull crushers as long as they start with lighter weights and focus on learning proper elbow positioning. Mastering technique is more important than lifting heavy loads early on.
Are skull crushers better for triceps size or strength?
The exercise is most commonly used for hypertrophy training, meaning it helps build muscle size. However, when progressively overloaded, skull crushers can also contribute to stronger elbow extension.
Why do many lifters prefer an EZ bar instead of a straight bar for skull crushers?
The angled handles of the EZ bar place the wrists in a more natural position. This grip often reduces wrist strain and makes the movement more comfortable, particularly during higher-rep sets.
