Hammer curl or bicep curl — both are great for building strong arms. They work the biceps but in different ways. Biceps curl primarily targets the biceps, while the hammer curl also involves the brachialis, the muscle underneath the biceps. If you want bigger arms, picking the right one matters. This guide compares the two to help you choose.
Hammer Curl or Bicep Curl: Key Differences
Hammer and bicep curls both grow your arms. But they hit the muscles in different ways. Below is a simple breakdown of how they differ — in grip, movement, and muscle focus.
| Feature | Hammer Curl | Bicep Curl |
|---|---|---|
| Grip | Palms facing each other, like a hammer grip | Palms facing up, classic grip |
| Main Target Muscle | Long head of the biceps, forearm muscles | Primarily targets the biceps |
| Involved Muscles | Forearm muscles, long head of the biceps | Primarily the biceps |
| Movement Direction | Keep the grip angle constant as you raise and lower the weight | Elbows bend as the weight is lifted and lowered |
| Training Focus | Increases forearm strength and grip while sculpting the biceps | Focuses on the biceps, increasing volume and definition |
When to Use Hammer Curl or Bicep Curl
Choose based on your goal — hammer curls or bicep curls. Each one works different muscles. Each also has its own benefits. This guide will help you decide which to use and when.
When to Use Hammer Curl
Hammer curls are a great choice in the following situations:
- To Improve Forearm Strength
Hammer curls are best for forearm strength. They work the forearm muscles more than bicep curls. Choose them if stronger forearms are your goal. - To Increase Grip Strength
Hammer curls use a neutral grip. This builds grip strength. It helps with deadlifts, rows, and pull-ups. - To Target the Long Head of the Biceps
Hammer curls work the long head of the biceps. This adds thickness to your arms. Great if you want bigger arms. - For a More Comprehensive Arm Workout
Hammer curls work both biceps and forearms. They give you a more balanced arm workout. Good choice for training multiple muscles at once.
When to Use Bicep Curl
Bicep curls are the go-to exercise in these scenarios:
- To Focus on Bicep Growth
Bicep curls are best for bicep size and definition. They target the biceps directly. Great if your goal is muscle growth. - To Improve Bicep Shape
Bicep curls shape and define the muscle. They use a full range of motion. This helps the biceps grow and look more detailed. - For Beginners
Bicep curls are easier for beginners. The grip and form are simple to learn. A good starting point for bicep training. - When You Want to Minimize Forearm Involvement
Bicep curls focus more on the biceps alone. They don’t work the forearms as much. This helps isolate the biceps better.
Hammer Curl or Bicep Curl: Which to Choose for Your Training Plan
Hammer curls and bicep curls both help build strong, defined arms. Each one works different muscles. Hammer curls work the forearms. They also target the long head of the biceps. Bicep curls, including those done with a bicep curl machine, mainly work the biceps. For the best results, use both in your workouts. This gives you a balanced and complete arm routine.
Sample Training Plan for Arms
| Exercise | Sets | Reps | Rest |
|---|---|---|---|
| Hammer Curl | 3 | 8-12 | 60 sec |
| Bicep Curl | 3 | 8-12 | 60 sec |
Notes: Alternate between hammer curls and bicep curls to target both forearms and biceps for balanced arm development.
Why Combine Both?
- Hammer curls build forearm strength training and arm thickness.
- Bicep curls grow the biceps and improve definition.
- Doing both builds stronger, bigger, and more balanced arms.
I’m Riley Williams, an editor for Leadman Fitness where we engineer bespoke strength equipment tailored to unique training goals. My expertise lies in home gym solutions, mobility tools, and injury-prevention gear, shaped by 8 years as a strength coach and rehab specialist. I know how subtle design flaws—a knurling pattern that blisters hands or a bolt that loosens mid-session—can derail progress.
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