Single-Arm Tricep Extension

Anton YefanovUpdated September 6, 2026

The single-arm tricep extension is overhead elbow extension done one side at a time. You sit upright on a flat bench, press a dumbbell to lockout with the working arm beside your ear, then bend at the elbow to lower the weight behind your head and press it straight back up. Holding the upper arm vertical puts the long head of the triceps on stretch, which is the whole reason to work overhead. Keeping the upper arm perpendicular to the floor is what preserves that stretch across the whole rep.

How to do the Single-Arm Tricep Extension

Sit upright on a flat bench with your feet flat and about hip-width apart.
Press one dumbbell overhead until the arm is straight and beside your ear.
Point the working elbow at the ceiling and rest your free hand on your thigh.
Bend the working elbow to lower the dumbbell behind your head.
Press the dumbbell back overhead without letting the upper arm drift.
Finish the set, then move the weight to the other arm and repeat.

Muscles worked

Primary:: Triceps

Why train it

Works one arm at a time so side-to-side differences show up clearly.
The overhead position loads the long head of the triceps under stretch.
Needs only a bench and a single dumbbell, so it fits minimal setups.

Common mistakes

Letting the elbow flare out to the side, which shortens the stretch on the long head.
Leaning the torso away from the working arm, which hides how much the shoulder is helping.
Choosing a weight that drags the arm out of position behind the head, which strains the elbow.
Cutting the descent short, which skips the stretched range the overhead position exists for.

Frequently asked questions

What muscles does the Single-Arm Tricep Extension work?

The Single-Arm Tricep Extension trains the triceps, and little else. No other group takes a meaningful share of the load, which is what makes this a clean way to target the triceps directly.

What equipment do I need for the Single-Arm Tricep Extension?

The Single-Arm Tricep Extension needs a dumbbell. Nothing beyond that is required to run the movement the way it is described above.

Is the Single-Arm Tricep Extension suitable for beginners?

Yes. The Single-Arm Tricep Extension is rated beginner: the pattern is quick to pick up and forgiving when a rep drifts. Start light and add weight once the form repeats itself without you thinking about it.

Can I do the Single-Arm Tricep Extension at home?

Yes, if you own a dumbbell. That is the whole requirement, and it is the reason this one travels well between a home setup and a gym floor.

How many sets and reps of the Single-Arm Tricep Extension should I do?

Three to four sets of 10 to 15 reps. Isolation work responds to reps and a controlled tempo rather than load, so stop each set a rep or two short of failure and keep the weight honest.

What are good alternatives to the Single-Arm Tricep Extension?

Bench Dips, Cable Bar Pushdown, and Machine Tricep Extension train the same primary muscles as the Single-Arm Tricep Extension. Pick whichever one suits the equipment in front of you.