How is the Kettlebell Concentration Curl different from the dumbbell version?

The movement and the target are the same, but the bell hangs below the handle, so your hand has to stop it swinging or tipping, which adds a grip and wrist challenge. The Dumbbell Concentration Curl is easier to load in small steps and to hold steady.

How do I progress when the next kettlebell is too heavy?

Kettlebells usually go up in bigger steps than dumbbells, commonly 4 kg (about 9 lb) at a time. Add reps over several sessions, slow the lowering phase or pause at the top, and move up a bell once you can do all your sets with clean form at the top of your rep range.

Will concentration curls give me a bigger biceps peak?

Not directly. The shape of the biceps, including its peak, is largely set by genetics, so no curl can change it, but growing the muscle with this or any curl makes the shape you have more visible.

Where should the Kettlebell Concentration Curl go in a workout?

Use it near the end of an upper-body or arm session, after heavier rows, pull-ups and two-arm curls. Sets of 8 to 15 reps per arm with a controlled tempo suit it well.

Kettlebell Concentration Curl

What Is the Kettlebell Concentration Curl?

Kettlebell Concentration Curl is an isolation exercise that primarily targets the biceps and also engages the brachialis, the brachioradialis and the grip muscles of the forearm. It is a beginner-level movement done one arm at a time from a seated position on a bench, with the back of the working arm braced against the inside of the thigh while a kettlebell, held by its handle, is curled from a hanging position up toward the chest.

Bracing the upper arm against the leg is the whole point of the exercise. With the arm pinned in place and the torso still, there is little room for momentum, so the elbow flexors do nearly all the work through the full range. The arm hangs forward of the body, much like on a preacher pad, and working one side at a time makes it easy to spot and even out a weaker arm. It is an accessory exercise rather than a main lift, and it usually sits near the end of an upper-body or arm session, after heavier pulling and two-arm curls.

The kettlebell changes the feel more than the target. Because the bell hangs below the handle instead of sitting beside the hand, the hand and wrist have to keep it from swinging or tipping, which adds a grip challenge that the Dumbbell Concentration Curl does not have. The underhand grip keeps the biceps as the main mover, while a neutral grip shifts more of the work to the brachialis and brachioradialis, as in the Dumbbell Hammer Curl.

The exercise suits beginners learning to curl strictly, lifters adding arm size, and anyone training at home with only kettlebells. The seated, braced position makes it easy to keep attention on the biceps, which is why many lifters use it to practice a full squeeze at the top. Anyone who struggles to keep the bell steady can start with the Band Concentration Curl or a light dumbbell version, and the standing Kettlebell Curl trains both arms with the same piece of equipment.

Muscles Worked

MuscleActivation

Biceps Brachii: Primary
Brachialis: High
Brachioradialis: Medium
Flexor Carpi Radialis: Low
Flexor Carpi Ulnaris: Low
Deltoid: Minimal
Erector Spinae: Minimal
Extensor Carpi Radialis: Minimal

Instructions

Sit on a flat bench with your feet flat on the floor, wider than hip width, and a kettlebell on the floor between your feet.
Lean forward from the hips with your back flat and grip the kettlebell handle in one hand with your palm facing forward, so the bell hangs below your hand.
Brace the back of your working upper arm, just above the elbow, against the inside of the same-side thigh near the knee.
Place your free hand on your opposite knee for support.
Let the arm hang almost straight toward the floor with the kettlebell still and clear of the floor.
Curl the kettlebell up toward your chest by bending the elbow, keeping the upper arm pinned to the thigh and the bell hanging steady under your hand.
Stop when your forearm is nearly vertical and squeeze the biceps for a moment, keeping your wrist straight.
Lower the kettlebell slowly along the same path until the elbow is almost straight, without letting the bell swing or touch the floor.
Complete all reps, then switch arms.

Common Mistakes

Elbow on top of the thigh
Propping the elbow on top of the leg turns the thigh into a lever that helps the weight up, so brace the back of the upper arm against the inside of the thigh instead.
Upper arm leaving the leg
Letting the elbow drift up or away from the thigh brings the shoulder and torso into the lift and takes tension off the biceps.
Swinging the bell
Letting the kettlebell swing under the hand or bouncing it out of the bottom adds momentum and makes the bell harder to control.
Bending the wrist
Curling the wrist up or letting it bend back under the hanging bell shifts work to the forearm and strains the wrist.
Cutting the bottom short
Stopping halfway down skips the stretched part of the range, so lower until the elbow is almost straight on every rep.
Using a bell that is too heavy
If the torso rocks, the shoulder shrugs or the wrist bends to finish a rep, the kettlebell is too heavy for this strict position.

Injuries

Kettlebell Concentration Curl is a low risk exercise when performed with proper technique. The load is light, the body is seated and the arm is braced, so there is little that can go wrong as long as the kettlebell stays under control.

The main strain point is the front of the elbow, where the biceps tendon attaches to the forearm. It takes the most stress while the bell is being lowered and at the bottom of the rep, so lower slowly and stop just short of a hard lockout rather than letting the arm snap straight. The wrist can also be strained if it bends back under the weight of the hanging bell, so keep it straight and choose a kettlebell you can hold steady. Keep your back flat and your free hand on the opposite knee to support the forward lean.

If the kettlebell is too heavy to control, regress to the Band Concentration Curl or a light Dumbbell Concentration Curl, which let you add weight in smaller steps. To progress, add reps, slow the lowering phase or pause at the top before moving to a heavier bell.

Stop the set if you feel sharp pain at the front of the elbow. A sudden pop, bruising, a visible change in the shape of the biceps or new weakness can signal a tendon tear and needs a clinician's assessment. Front-of-elbow pain that keeps coming back with curls is a reason to reduce the load and get it checked.

Overview

Primary Focus: Biceps
Equipment: Kettlebell and bench
Modality: Strength
Difficulty: Beginner

Alternative Exercises

Frequently Asked Questions

Q: How is the Kettlebell Concentration Curl different from the dumbbell version?: The movement and the target are the same, but the bell hangs below the handle, so your hand has to stop it swinging or tipping, which adds a grip and wrist challenge. The Dumbbell Concentration Curl is easier to load in small steps and to hold steady.
Q: How do I progress when the next kettlebell is too heavy?: Kettlebells usually go up in bigger steps than dumbbells, commonly 4 kg (about 9 lb) at a time. Add reps over several sessions, slow the lowering phase or pause at the top, and move up a bell once you can do all your sets with clean form at the top of your rep range.
Q: Will concentration curls give me a bigger biceps peak?: Not directly. The shape of the biceps, including its peak, is largely set by genetics, so no curl can change it, but growing the muscle with this or any curl makes the shape you have more visible.
Q: Where should the Kettlebell Concentration Curl go in a workout?: Use it near the end of an upper-body or arm session, after heavier rows, pull-ups and two-arm curls. Sets of 8 to 15 reps per arm with a controlled tempo suit it well.