Seated Dumbbell Triceps Extension

About This Exercise

Classic seated overhead triceps isolation: sit upright on a bench (with back support if available), hold one dumbbell with both hands by the inner plate, raise it overhead, then lower behind the head by bending only at the elbows, then extend back overhead. The seated setup eliminates the core-stabilisation fatigue cost that the standing variant carries (where the core works hard to prevent backward lean under the load). For hypertrophy programming where the goal is isolated triceps work, the seated variant gives cleaner triceps focus and lower compound fatigue. Distinct from Standing Dumbbell Triceps Extension (standing; recruits core), Cable Rope Overhead Triceps Extension (rope variant; typically standing), Seated Bent-Over Two-Arm Dumbbell Triceps Extension (bent-over kickback-style; different mechanic), and Lying Triceps Extensions / Skull Crushers (lying; different biomechanic).

1Setup

Sit upright on a bench (preferably with back support — an upright back-supported bench or a low-back bench at 80-90 degrees works best). Feet flat on the floor. Hold one dumbbell vertically with both hands cupped under the inner plate (palms pressing up against the underside of the upper plate, thumbs and index fingers around the handle). Press the dumbbell straight up overhead so the arms are vertical, biceps alongside the ears. This is the start position.

2Execution

Inhaling, lower the dumbbell behind the head in a controlled arc by bending only at the elbows. Keep the upper arms vertical and as close to the head as possible — do not let the elbows flare wide. Lower until the forearms are roughly parallel to the floor (or until you feel a strong stretch through the triceps). Pause briefly, then exhale and extend the elbows to press the dumbbell back overhead, returning the arms to vertical. The motion is in the elbows, not the shoulders — the upper arms stay vertical throughout.

Pro Tips

• Upper arms stay vertical and close to the head — the elbows bend, the upper arms do not move
• Cup the dumbbell with both hands by the inner plate; fingers and thumbs locked around the handle for safety. A heavy DB behind your head is not the moment for a loose grip.
• Sit with back support if possible — that is the whole point of choosing seated over standing for this lift; the back support locks the trunk and removes core-stabilisation as a fatigue source
• Tempo: 2-3s eccentric, brief pause at full stretch behind head, controlled press back overhead
• For hypertrophy programming: the seated overhead variant is the classic tricep mass-builder; it pairs well with skull crushers (lying, different angle) and tricep pushdowns (cable, different angle) for full triceps coverage