Seated Dumbbell Skull Crusher

Starting position

1. Sit on a bench, preferably one with a backrest. Feet flat on the floor, slightly wider than hip width.
2. Hold a dumbbell with both hands: palms pressed against the top plate, thumbs around the handle.
3. Press the dumbbell overhead with straight arms, elbows pointing forward.
4. Chest open, shoulder blades down, core tight, eyes looking straight ahead.

Execution

1. Inhale and bend only at the elbows, lowering the dumbbell behind your head in an arc.
2. Go down to about 90° at the elbow or a little deeper — until you feel the triceps stretch.
3. Exhale and extend your arms firmly but under control, bringing the dumbbell back up.
4. Your upper arms stay nearly vertical and still throughout the set.

Common mistakes

• Moving the shoulders instead of the elbows — the dumbbell gets pressed and the triceps underwork.
• Elbows spread wide — less effective and harder on the joints.
• Leaning back — the lower back arches and gets overloaded.
• Bouncing at the bottom — the triceps tendons take a jolt.

Beginner tips

• Use a bench with a backrest if you have one — it makes it easier to keep your back straight.
• Do 10–12 reps with a weight that lets you keep your elbows in.
• If your shoulder feels uncomfortable, shorten the depth.

Alternatives

• Seated Barbell Skull Crusher — handy if you have an EZ bar
• Triceps Rope Pushdown — even load through the full range
• Diamond Push-Ups — an option with no equipment