Concentration Curl: Form Guide, Muscles and Mistakes
Load card
- Equipment
- Dumbbell
- Muscle group
- Biceps
- Main muscles
- biceps brachii
- Also working
- brachialis
- Mechanics
- Isolation
- Pattern
- Elbow flexion
- Level
- Beginner
The concentration curl is a beginner isolation exercise that targets the biceps brachii using a single dumbbell. By bracing your arm against your leg, you eliminate momentum and focus entirely on elbow flexion.
This movement strictly isolates the biceps while recruiting the brachialis as a supporting muscle. It is an effective way to train your arms without relying on your shoulders or back to move the weight.
How to do it
Sit on the edge of a bench with your feet flat on the floor and a dumbbell between your legs. Hinge forward and press the back of your working arm against the inside of your thigh.
- Grip the dumbbell with your palm facing up.
- Let your arm hang straight down so you feel a stretch in your biceps.
- Curl the dumbbell upward toward your shoulder by bending your elbow.
- Squeeze your biceps hard at the top of the movement.
- Lower the weight slowly and under control back to the starting position.
Sets, reps and load
Start with 3 sets of 8 to 12 repetitions per arm. Rest for 60 to 90 seconds between sets to allow your arms to recover.
Choose a dumbbell that feels challenging for the last two reps while allowing you to maintain proper form.
Common mistakes
- Using momentum. Keep your torso still and rely only on your biceps to lift the weight.
- Curling the wrist. Keep your wrist in a neutral position so your biceps do the work instead of your forearms.
- Short range of motion. Lower the dumbbell until your arm is fully extended at the bottom.
- Lifting the elbow. Keep the back of your arm pressed firmly against your inner thigh the entire time.
- Rushing the descent. Take two to three seconds to lower the dumbbell to maximize tension.
Make it easier or harder
Easier
- Seated dumbbell curl without bracing the arm
- Standing dumbbell hammer curl
Harder
- Slow eccentric concentration curl
- Pause concentration curl
Swaps and related biceps exercises
Same muscle group with different equipment:
- Resistance Band Bicep Curl Resistance band
More dumbbell options:
- Dumbbell Bicep Curl Elbow flexion
- Hammer Curl Elbow flexion, neutral grip
- Incline Dumbbell Curl Elbow flexion, shoulder extended
Browse all dumbbell exercises or every biceps exercise.
When to see a doctor or physio
- Sharp pain in the elbow joint during the curl.
- Tingling or numbness radiating down your forearm.
- A sudden tearing sensation in the biceps muscle.
This page is general training information, not medical advice. If you are new to strength training, managing a health condition, pregnant or coming back from an injury, check with a doctor or physio first.
How this page was made. Exercise data (equipment, muscles, mechanics, level) compiled by the Unite Journal Crew as a general anatomy guide, cross-checked against the public-domain free-exercise-db list. Text drafted with AI assistance and edited by the crew; see our house rules. Last checked October 2026.