Lying Dumbbell Tricep Extension
This is a lying triceps isolation move where you hold a dumbbell in each hand above your chest and lower them together toward the sides of your head, then press them back up. The overhead arm position also asks your shoulders to hold steady and gives your chest a light stretch, which is why both show up as secondary muscles here even though the triceps do almost all the work. It suits anyone past the beginner stage who already curls and presses comfortably and wants a dedicated triceps finisher.
Why it works
Lowering the dumbbells to the sides of your head, rather than crossing them together at your forehead, keeps each arm working through its own straight line instead of sharing a single bar path. That means each triceps has to control its own dumbbell independently, which builds a bit more stability than a barbell version where the bar forces both arms to move in sync. Holding the arms overhead the entire set also keeps the shoulders working isometrically to keep the weights from drifting.
Set up
- Lie flat on a bench with your feet planted on the floor and a light-to-moderate dumbbell in each hand.
- Press the dumbbells up above your chest so your arms are fully extended, palms facing each other.
- Brace your core so your lower back stays settled against the bench.
- Fix your upper arms in place before starting the first rep.
How to do it
- Start with both dumbbells locked out directly above your shoulders.
- Bend your elbows and lower the dumbbells at the same time toward the sides of your head, keeping your upper arms still.
- Lower until you feel a solid stretch in the back of your upper arms, without letting the weights drop past a comfortable range.
- Extend your elbows to press both dumbbells back up over your chest.
- Keep the same tempo on both arms so one doesn't finish ahead of the other.
- Repeat for the set.
Form cues
- Elbows stay narrow and pointed forward, not flared to the sides.
- Lower both dumbbells at the same pace.
- Keep your upper arms still, only the forearms travel.
- Press back to full extension without locking the elbows out violently.
Breathing: Inhale as you lower the dumbbells toward your head, exhale as you press them back up.
Common mistakes
Letting the elbows flare outward as the weights lower, which shifts stress off the triceps and onto the shoulders.
Fix: Keep the elbows tracking forward and roughly shoulder-width apart through the whole rep.
Lowering one arm faster than the other, which can twist the torso to compensate.
Fix: Slow down and match the pace of both arms, using a lighter weight if needed to keep them in sync.
Using a weight so heavy that the shoulders take over to help press it back up.
Fix: Drop the load until the triceps alone can complete the full range without shoulder assistance.
How to program it
- As a triceps isolation move, 2 to 3 sets of 10 to 12 reps once or twice a week fits most training plans well.
- Place it after your heavier pressing work in a push session, since it's meant to finish the muscle rather than build raw strength.
- Increase the dumbbell weight only once both arms move together smoothly for every rep.
Safety notes
- Warm your shoulders up before loading this movement, since they hold an overhead position under tension for the whole set.
- Choose a bench with enough width or use a spotter for heavier loads, since dropping a dumbbell near your head is a real risk.
- Stop if you feel shoulder pinching rather than pushing through a heavier weight.
Exercise profile
- Force
- Push
- Mechanics
- Isolation
- Category
- Strength
Frequently asked questions
How many sets and reps for the lying dumbbell tricep extension?
Two to three sets of 10 to 12 reps, once or twice a week, works well as a triceps finisher placed after your main pressing work.
What can I do at home without a bench?
A standing dumbbell triceps extension trains the same muscle overhead without needing to lie down, and works fine on the floor or standing in open space.
Why does one arm feel weaker during this exercise?
That's common and usually just reflects a real strength difference between arms. Slow the tempo down and let the weaker arm set the pace instead of rushing to match the stronger one.
Lying dumbbell extension vs dumbbell skullcrusher: what's different?
Both are lying triceps moves with dumbbells. A skullcrusher usually brings the dumbbells together toward the forehead, while this version lowers them independently to the sides of the head, asking each arm to control its own path.