Muscles worked
What the concentration curl trains
Tap a muscle to see just that one and what it does in the lift.
Before the first rep
How to set up
- 01
Sit at the end of a bench. Sit near the end of a flat bench with your feet flat on the floor, a bit wider than your hips, so there is room for the dumbbell to hang between your legs.
- 02
Pick up the dumbbell. Hold one dumbbell in the middle of the handle with a full underhand grip, palm facing your other leg, wrist straight in line with your forearm.
- 03
Lean forward. Hinge forward from your hips with your back flat, not rounded. Rest your free hand on your other thigh for support.
- 04
Brace your arm. Press the back of your upper arm, just above the elbow, against the inside of your thigh on the same side. Your elbow sits close to your knee.
- 05
Start at a straight arm. Let the dumbbell hang with your elbow straight and your upper arm pointing toward the floor. This is where every rep starts and ends.
Step by step
How to do the concentration curl
- 01
Brace. Take a breath and settle your upper arm firmly against your thigh. From here on, only your forearm moves.
- 02
Curl. Bend your elbow and bring the dumbbell up toward the front of your shoulder, keeping your palm turned up and your wrist straight.
- 03
Squeeze at the top. Stop when your elbow is fully bent and squeeze your biceps for a moment. Your upper arm stays pressed against your thigh; if it lifts off, the shoulder is taking over.
- 04
Lower slowly. Take about two to three seconds to lower the dumbbell, keeping tension in your biceps the whole way down.
- 05
Finish at a straight arm. Straighten your elbow fully at the bottom before the next rep, without letting the weight drop or your torso bob.
- 06
Switch arms. Do all your reps on one arm, then switch. Starting with your weaker arm and matching its reps on the other side keeps both arms even.
Cues to say in your head
- Arm pinned to thigh
- Palm up the whole way
- Curl to your shoulder
- Slow on the way down
- Straight arm at the bottom
- Torso stays still
Fix these first
Common mistakes
Upper arm lifting off your thigh
Keep the back of your upper arm pressed into your inner thigh for the whole rep. If it peels away at the top, the front of the shoulder is helping and the weight is probably too heavy.
Rocking your torso to lift the weight
Hold your forward lean still and move only your forearm. If you have to sit up or rock back to finish a rep, use a lighter dumbbell.
Half reps that stop short of a straight arm
Lower all the way to a straight elbow on every rep. The bottom of the curl is part of the work, not a rest.
Dropping the weight on the way down
Control the lowering for two to three seconds. Letting the dumbbell fall wastes half the rep and is hard on the elbow.
Rounding your back over the dumbbell
Lean forward by hinging at your hips with a flat back, and rest your free hand on your other thigh to hold your position.
Wrist curling in or bending back
Keep your wrist straight and in line with your forearm. A bent wrist moves the work to your forearm and can strain the joint.
Stay safe
Pick a dumbbell you can lower under control, and lower to a straight arm smoothly rather than letting the weight snap your elbow straight. If you cannot finish a rep, lower the dumbbell slowly to a straight arm and set it on the floor between your feet; do not drop it. Stop the set if you feel sharp pain in the front of your elbow or shoulder rather than a normal muscle burn, and if pain keeps coming back, or you hear a pop with sudden pain and bruising, stop training the arm and see a doctor or physical therapist.
Programming
Sets, reps and how much weight
| Goal | Sets | Reps | Load | Rest |
|---|---|---|---|---|
| Muscle | 3 to 4 | 8 to 12 | 65–75% 1RM | 1 to 2 min |
| Endurance | 2 to 3 | 15 to 20 | 50–60% 1RM | 45 to 90 sec |
| Technique | 2 to 3 | 10 to 12 | 50–60% 1RM | 1 min |
Plan your next session
Put in a recent set. You get working weights for your goal, a warm-up and the plates to load.
Estimated 1RM 216 lb
Endurance sets
108–129lb
2 to 3 sets of 15 to 20 reps, 45 to 90 sec rest. A lighter, steady set that works well as a finisher at the end of an arm or pull day.
Estimates use the Epley formula and work best from sets of 3 to 8 reps. Treat them as a starting point and adjust by how the first working set moves.
Questions
Concentration Curl questions
What muscles does the concentration curl work?
Mainly the biceps, with the brachialis underneath and the brachioradialis in the forearm helping bend the elbow. Your grip holds the dumbbell, and your lower back holds your forward lean steady.
Concentration curl vs preacher curl: which is better?
Neither is clearly better: both brace your upper arm so you cannot swing the weight. The concentration curl needs only a dumbbell and a bench and trains one arm at a time; the preacher curl needs a preacher bench but can be done with a bar and both arms. Pick the one your gym and your elbows suit, or rotate them.
Where should my elbow be on a concentration curl?
Press the back of your upper arm, just above the elbow, against the inside of your thigh on the same side, with the elbow near your knee. Keep it there for the whole rep so only your forearm moves.
Can you do concentration curls standing?
Yes. Stand and hinge forward at the hips with a flat back, let the working arm hang straight down, and rest your free hand on a bench or your thigh. The seated version is easier to hold still, so start there.
How many sets and reps of concentration curls should I do?
For muscle growth, 3 to 4 sets of 8 to 12 reps per arm, taken close to failure, works well for most people. Add reps first, then move up to the next dumbbell.
Train in Protocol
Log your concentration curl by voice. Protocol tracks the rest.
Your last session shows up before every set, warm-ups and plates are worked out for you, and your coach sees every lift next to your sleep and recovery.