Dumbbell curl

Also known as: Biceps curl

The classic isolation exercise for the biceps.

What it is

Curling a dumbbell from a straight arm to full flexion, isolating the biceps. A simple, effective accessory for arm size.

Muscles worked

Primary: Biceps. Secondary: Forearms, Front deltoids.

How to perform it

  1. Stand or sit holding dumbbells at your sides, palms facing forward (or neutral to start).
  2. Keep your elbows pinned to your sides and your torso still.
  3. Curl the weight up by flexing the elbow, squeezing the biceps at the top.
  4. Lower under control all the way to a straight arm before the next rep.

Common form faults

  • Swinging the torso to heave the weight up. Keep the torso still and elbows fixed; if you have to swing, the weight is too heavy.
  • Cutting the range short at the bottom or top. Straighten the arm fully each rep and curl to full flexion — partial reps leave gains on the table.

Programming

An accessory, not a main lift — the big pulls already train the biceps. Higher reps (8–15) with strict form work well; leave the ego at the door.

Variations & substitutions

Frequently asked questions

Do I even need direct biceps work?
Rows and pull-ups already train the biceps heavily, so they aren't essential — but a little direct curl work is an efficient way to add arm size if that's a goal.
Should I curl both arms together or alternate?
Both are fine. Alternating lets you focus on each arm and often allows slightly stricter form; curling together is more time-efficient. Pick whichever keeps your form clean.

Written and reviewed by Mathew Beale MSc Biotechnology, University of Reading.

Last reviewed: