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  5. Arms
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  7. Dumbbell Single Arm Wrist Curl

Exercise guide

Dumbbell Single Arm Wrist Curl

  • Beginner
  • Isolation
  • Rep-based
  • Lower arms

This isolation exercise specifically targets the wrist flexors on the underside of the forearm to build grip strength and forearm mass. Working unilaterally allows for a greater mind-muscle connection and helps correct strength imbalances between arms.

Reviewed by the Crucible Fit team · Updated June 2026

Watch the Dumbbell Single Arm Wrist Curl demonstrationVideo and instructions for every movement are in the Crucible Fit app.

Muscles worked

Primary

  • Forearms

Equipment

  • Dumbbell

Setup

  1. Sit on a bench and hold a dumbbell in one hand with an underhand (supinated) grip.
  2. Rest your forearm flat against your thigh or the edge of a flat bench, allowing your wrist to hang off the edge.
  3. Position your feet firmly on the floor and use your non-working hand to stabilize your body if needed.

How to do it

  1. Inhale as you slowly lower the dumbbell toward the floor by extending your wrist as far as comfortably possible.
  2. Exhale as you curl the dumbbell upward by flexing your wrist, bringing the weight toward your forearm.
  3. Squeeze the forearm muscles at the peak of the contraction for one second.
  4. Lower the weight back to the starting position using a controlled 2-second tempo.

Form checklist

  • Keep your forearm glued to your thigh or the bench; do not let the elbow lift.
  • Ensure the movement comes strictly from the wrist, not the bicep or shoulder.
  • Move through a full range of motion, from a deep stretch at the bottom to a full squeeze at the top.
  • Maintain a neutral spine and avoid leaning into the movement to create momentum.

Pro tips

  • At the bottom of the movement, allow the dumbbell to roll slightly down into your fingertips to maximize the stretch on the flexors.
  • Focus on 'rolling' the weight back into your palm before initiating the actual wrist curl to engage the deep finger flexors.

Make it harder

  • Increase the eccentric phase to 4 seconds to maximize time under tension.
  • Add a 5-second isometric hold at the top of every third repetition.

Frequently asked

What muscles does the dumbbell single arm wrist curl work?
The dumbbell single arm wrist curl primarily targets the forearms.
What equipment do you need for the dumbbell single arm wrist curl?
The dumbbell single arm wrist curl uses dumbbell.
Is the dumbbell single arm wrist curl good for beginners?
Yes. The dumbbell single arm wrist curl is a beginner-friendly movement and a strong foundation to build on.

Related exercises

  • Band Reverse Wrist CurlBeginner · forearms
  • Band Wrist CurlBeginner · forearms
  • Barbell Behind Back Finger CurlBeginner · forearms
  • Barbell Palms Down Wrist Curl Over A BenchIntermediate · forearms

Train it with Crucible Fit.

Every movement in this library is in the app with video and instructions, ready for your own sessions on the days between Crucibles. Your first Crucible is on us.

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