If you are looking for a single arm exercise that delivers size, strength, and joint-friendly mechanics, hammer curls should be near the top of your list. As a professional trainer, I know the benefits. And today I want to explain why hammer curls are not just a go-to bicep builder but one of the most effective and versatile arm movements you can include in your training.
This is not just about aesthetics. Hammer curls target more muscles than most people realize, and they do it in a way that supports real-world strength, joint health, and performance across sports.
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What Are Hammer Curls?
Hammer curls are a variation of the traditional bicep curl, performed with a neutral grip. That means your palms face each other throughout the movement. Imagine holding a dumbbell so that the dumbbell head and your forearm form the shape of a hammer. That is where the name comes from.
Unlike a regular bicep curl, which involves turning the wrist into a supinated position, hammer curls keep the wrist neutral. This small shift completely changes the muscle recruitment pattern, making hammer curls an extremely effective upper arm and forearm exercise.
And all you need is a pair of dumbbells.
Start with your hands hanging naturally at your side, holding the dumbbells as shown. Then lift them to your chest, keeping your wrists neutral, neither underhanded nor overhanded to the top of the movement.
Then control the release so your arms move at the same tempo back to your sides.
Muscles Worked in Dumbbell Hammer Curls
Most people think hammer curls only work the biceps. That is only part of the picture.
When you perform hammer curls, you are training both heads of the biceps: the short head and the long head. The long head is emphasized more due to the neutral grip, which helps build arm width and improve the appearance of your arms from the side.
More importantly, hammer curls strongly activate two other major muscles:
- Brachialis: This is a deep muscle located underneath the biceps. It is the strongest elbow flexor in the arm. As it grows, it pushes the bicep up, creating the look of a larger, fuller upper arm.
- Brachioradialis: This muscle runs down the top of your forearm. It contributes to the thick, muscular forearm look seen in elite lifters. Hammer curls target the brachioradialis effectively, making your arms look more complete from wrist to shoulder.
By training hammer curls consistently, you are not just isolating the biceps. You are strengthening the entire elbow flexor chain, which supports stronger performance in compound lifts and athletic movements.
Why HC Workouts Improve Performance
If you are a powerlifter, strongman competitor, or field sport athlete, you already know how important arm stability, grip strength, and elbow health are. Hammer curls help develop all of those.
Think about how many sport-specific movements involve pulling, lifting, or carrying with a neutral grip. Hammer curls directly train those mechanics. They reinforce functional strength that carries over to your deadlift, rows, and even pressing movements.
In addition, hammer curls are more joint-friendly than many common bicep exercises. Supinated curls often cause wrist or elbow discomfort for lifters, especially under heavy weight. A neutral grip places less stress on the wrist and elbow joints while still delivering strong muscle activation.
Should You Swing the Weights?
This might sound controversial, but I do not mind a little swing in the hammer curl — especially for more experienced lifters.
Why? Because even if you use momentum to bring the weight up, the real benefit comes from controlling the weight on the way down. That is the eccentric phase, and it is where most of the muscle-building stimulus occurs.
If you swing the weight up and then slow it down under control, you are still training effectively. Eccentric loading is one of the most proven ways to build size and strength.
So yes, cheat a little if needed. Just make sure you own the weight on the way down.
Hammer Curl Variations
Once you have nailed the basic standing hammer curl, here are a few hammer curl variations to challenge your arms and add new stimulus:
- Cheat Hammer Curls: Use some momentum on the way up, then slow down and control the eccentric phase. This overloads the muscles for added growth.
- Incline Hammer Curls: Perform the curl while leaning back on a bench. This increases the stretch on the long head of the bicep and changes the angle of resistance.
- Preacher Hammer Curls: Use a preacher bench and a neutral grip to isolate the arms. This variation removes momentum and requires strict form.
- Reverse Curls: Use a barbell or EZ bar with an overhand grip. This targets the same muscles as hammer curls but adds extra forearm activation.
Each variation brings unique benefits. Rotate them into your routine to avoid plateaus and keep progressing.
Here's a quick demo of how to do cheat curls.
The benefit to using a “cheat” hammer curl? It's a good way to get the benefits of the controlled downward motion without challenging the curl itself as much. That's especially beneficial for targeting the eccentric phase (and building serious muscle growth).
You might notice one key variation missing from these recommendations. I cover that in my guide on hammer curls vs. bicep curls. Hint: The key is in the grip, and that changes which muscles are targeted.
Final Thoughts on Hammer Curls
If I had to choose only a few exercises for arm development, hammer curls would definitely be one of them. They are simple, effective, and target more muscles than most lifters realize.
Whether your goal is to build bigger arms, improve your grip and elbow health, or boost overall upper body performance, hammer curls deserve a place in your training. They are easy to learn, joint-friendly, and incredibly effective when done with intent.
Hammer curls may not be the flashiest exercise in the gym, but they are one of the most powerful tools you can use to build strong, thick, and functional arms.
