Dumbbell Single Arm Tricep Extension

Target muscles

The triceps brachii — especially the long head — is loaded through its greatest stretch position thanks to the overhead arm position. The medial and lateral heads contribute. The serratus anterior holds the scapula stable. The trunk braces against the overhead load. The grip holds the dumbbell. As a single-arm exercise, the load can be precisely controlled per side, exposing strength imbalances.

How to perform

Setup

Stand or sit. Hold a dumbbell in one hand and raise the arm straight overhead. The other hand can rest at the side or on the working bicep for stability. Trunk braced.

Execution

Bend the elbow to lower the dumbbell behind the head until the forearm is roughly parallel to the floor. The upper arm stays vertical throughout — it doesn't drop forward or out. Squeeze the triceps at the bottom stretch for a moment. Extend the elbow to press the dumbbell back overhead to full lockout. Slow controlled tempo, especially on the descent.

Common mistakes

• Letting the upper arm drop forward. Keep it close to the head.
• Hyperextending the lower back to support overhead load. Brace the abs.
• Going too heavy. The triceps work through a small lever in this position.
• Cutting the bottom stretch. Let the dumbbell go all the way down.
• Bouncing into the bottom.

Progressions and regressions

Regress to two-handed overhead triceps extensions. Build the overhead position with shoulder mobility work. To progress, work pause extensions (3-second pause at the stretch), or use a heavier dumbbell for strict-form sets.

Programming notes

Excellent triceps accessory. 3 sets of 10-12 reps per side. Two times a week. Pair with pushdowns to hit the long and lateral heads in different stretched positions.