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  7. Dumbbell Lying Triceps Extension

Exercise guide

Dumbbell Lying Triceps Extension

  • Intermediate
  • Isolation
  • Rep-based
  • Upper arms

The dumbbell lying triceps extension is a premier isolation exercise that targets all three heads of the triceps, specifically emphasizing the long head for maximum arm thickness. By using dumbbells, you ensure balanced development and a greater range of motion compared to a barbell.

Reviewed by the Crucible team · Updated June 2026

Watch the Dumbbell Lying Triceps Extension demonstrationGuided video and your full workout live in the Crucible app.

Muscles worked

Primary

  • Triceps

Secondary

  • Biceps
  • Deltoids

Equipment

  • Dumbbell

Setup

  1. Lie flat on a bench with your feet firmly planted on the floor for stability.
  2. Hold a dumbbell in each hand using a neutral grip (palms facing each other).
  3. Extend your arms straight up over your shoulders, then tilt them back about 15 degrees toward your head to maintain constant tension on the triceps.

How to do it

  1. Inhale and slowly lower the dumbbells by bending only at the elbows until they are positioned near the sides of your forehead or ears.
  2. Keep your upper arms stationary and your elbows tucked in throughout the descent.
  3. Exhale as you use your triceps to extend your arms back to the starting tilted position.
  4. Perform the movement with a controlled tempo, taking 2 seconds to lower the weight and 1 second to extend.

Form checklist

  • Keep your elbows pointing forward; do not let them flare out to the sides.
  • Ensure only your forearms are moving; your upper arms should remain fixed.
  • Maintain a neutral, strong wrist position throughout the set.
  • Keep your lower back pressed against the bench to avoid arching.

Pro tips

  • Focus on the deep stretch at the bottom of the movement to maximize recruitment of the triceps' long head.
  • Avoid fully locking out your elbows at the top to keep the tension strictly on the muscle rather than the joint.

Make it harder

  • Perform the exercise on a decline bench to increase the range of motion and the stretch on the triceps.
  • Pause for one second at the bottom of each rep to eliminate momentum and increase time under tension.

Frequently asked

What muscles does the dumbbell lying triceps extension work?
The dumbbell lying triceps extension primarily targets the triceps, and also works the biceps and deltoids as secondary muscles.
What equipment do you need for the dumbbell lying triceps extension?
The dumbbell lying triceps extension uses dumbbell.
Is the dumbbell lying triceps extension good for beginners?
The dumbbell lying triceps extension is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.

Related exercises

  • Arm Double CrossoverIntermediate · biceps, deltoids, and triceps
  • Aztec Push UpIntermediate · pectorals, serratus anterior, and triceps
  • Band Assisted DipIntermediate · triceps
  • Band Bent Over One Arm Neutral Grip KickbackBeginner · triceps

Train this with a plan, not guesswork

Crucible builds the dumbbell lying triceps extension into a precise program around your body, equipment, location, and time.

Download on the App Store