FormTwin › Exercises › Bicep Curl

What muscles does the Bicep Curl work?

The bicep curl is the most direct arm exercise there is — an isolation move that targets the biceps for size and strength.

Primary muscles worked

Secondary muscles worked

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How to do the Bicep Curl

  1. Stand tall with a dumbbell in each hand, palms forward.
  2. Keep your elbows pinned to your sides.
  3. Curl the weights up by contracting the biceps.
  4. Squeeze at the top, then lower slowly under control.

Common mistakes

Variations

Hammer curlBarbell curlPreacher curl

Frequently asked questions

What muscles do bicep curls work?

Bicep curls target the biceps brachii, with the brachialis and forearm muscles assisting. Hammer curls (neutral grip) shift more emphasis onto the brachialis and forearms.

Do curls build arm size?

Curls build the biceps, but the triceps make up about two-thirds of your upper-arm size — so for bigger arms, train pressing and triceps work at least as hard as curls.

How heavy should bicep curls be?

Heavy enough that the last couple of reps are hard while keeping your elbows still and torso quiet. If you have to swing, the weight is too heavy to actually target the biceps.

Related exercises

DeadliftBack SquatBench PressPull-UpPush-Up

This guide is general fitness information, not medical advice. Muscle involvement varies with form, grip and individual anatomy. Consult a professional before starting a new program.