# Kettlebell Skull Crusher

A lying triceps isolation exercise with one kettlebell held in both hands on a flat bench. Builds elbow extension strength and arm size.

- Intermediate · Isolation
- Equipment: Kettlebell, Flat bench
- HD video: https://media.seto.fit/exercises/kettlebell-skull-crusher/video/male.mp4
- HTML: https://seto.fit/exercises/kettlebell-skull-crusher/

## Muscles worked

- Triceps: 10/10
- Forearms: 4/10
- Front delts: 3/10

## How to do the Kettlebell Skull Crusher

1. Lie on a bench, feet flat, holding one kettlebell above your shoulders with both hands.
2. Bend your elbows, lowering the kettlebell toward your forehead.
3. Straighten your arms fully to return the kettlebell to the starting position.
4. Keep your upper arms fixed in place throughout the movement.

### Full technique — 6 steps

1. Lie flat on a bench with feet planted and hold one kettlebell above your shoulders.
2. Wrap both hands around the round part of the kettlebell, leaving the handle free.
3. Straighten your arms and set your upper arms nearly vertical with elbows pointing upward.
4. Bend your elbows to lower the kettlebell toward your forehead.
5. Stop when your elbows reach a deep bend and the kettlebell is close without touching.
6. Extend your elbows to drive the kettlebell back to the start over your shoulders.

## Common mistakes

- Elbows flaring wide apart
- Upper arms drifting backward excessively
- Turning it into a press
- Cutting the bottom range short

## Form cues

- Move only at elbows
- Keep upper arms fixed
- Keep wrists straight
- Lower toward forehead

## How much to do

- **Strength**: 3–4 sets of 6–8 reps · rest 2 min · 2 reps in reserve · lower 3 s, lift 1 s
- **Muscle growth** (best fit): 3–4 sets of 8–12 reps · rest 1 min 15 s · 2–3 reps in reserve · lower 3 s, lift 1 s
- **Endurance** (good fit): 2–3 sets of 15–20 reps · rest 45 s · 3–4 reps in reserve · lower 2 s, lift 1 s

Reps in reserve: how many more you could still do when you end the set.

## Substitutes by equipment

Same muscles, same movement — pick the version you have the gear for.

- **Cable machine**: [Cable Overhead Triceps Extension (EZ Bar)](https://seto.fit/exercises/cable-overhead-triceps-extension-ez-bar/), [Triceps Pushdown (Reverse Grip)](https://seto.fit/exercises/triceps-pushdown-reverse-grip/)
- **Dumbbells**: [Incline Dumbbell Overhead Triceps Extension](https://seto.fit/exercises/incline-dumbbell-overhead-triceps-extension/), [Dumbbell Floor Skull Crusher](https://seto.fit/exercises/dumbbell-floor-skull-crusher/)
- **Resistance bands**: [Resistance Band Overhead Triceps Extension](https://seto.fit/exercises/resistance-band-overhead-triceps-extension/), [Single Arm Overhead Resistance Band Triceps Extension](https://seto.fit/exercises/single-arm-overhead-resistance-band-triceps-extension/)
- **No equipment**: [EZ Bar Overhead Triceps Extension](https://seto.fit/exercises/ez-bar-overhead-triceps-extension/), [Kneeling Bodyweight Triceps Extension](https://seto.fit/exercises/kneeling-bodyweight-triceps-extension/)

## Where to start and where to go next

Same muscles, same movement. Too hard for now — step down; once it gets easy — step up.

- Easier: [Triceps Pushdown (Rope)](https://seto.fit/exercises/triceps-pushdown-rope/) — Beginner
- Easier: [Kettlebell Overhead Triceps Extension](https://seto.fit/exercises/kettlebell-overhead-triceps-extension/) — Beginner
- **This exercise: Kettlebell Skull Crusher — Intermediate**
- Harder: [Bodyweight Triceps Extension](https://seto.fit/exercises/bodyweight-triceps-extension/) — 70% of bodyweight

## Quick answers

### What muscles does the Kettlebell Skull Crusher work?

Primary: Triceps 10/10. Also works: Forearms 4/10, Front delts 3/10.

### When should I do the Kettlebell Skull Crusher in a workout?

Finisher. Goes last, once the heavy work is done. ≈ 6 min with rest.

### How many sets and reps of the Kettlebell Skull Crusher?

Strength: 3–4 sets of 6–8 reps, rest 2 min, 2 reps in reserve. Muscle growth: 3–4 sets of 8–12 reps, rest 1 min 15 s, 2–3 reps in reserve. Endurance: 2–3 sets of 15–20 reps, rest 45 s, 3–4 reps in reserve.

### What can I do instead of the Kettlebell Skull Crusher?

Cable machine: Cable Overhead Triceps Extension (EZ Bar), Triceps Pushdown (Reverse Grip). Dumbbells: Incline Dumbbell Overhead Triceps Extension, Dumbbell Floor Skull Crusher. Resistance bands: Resistance Band Overhead Triceps Extension, Single Arm Overhead Resistance Band Triceps Extension. No equipment: EZ Bar Overhead Triceps Extension, Kneeling Bodyweight Triceps Extension.

### What is an easier version of the Kettlebell Skull Crusher?

Kettlebell Overhead Triceps Extension (Beginner), Triceps Pushdown (Rope) (Beginner).

### What is a harder version of the Kettlebell Skull Crusher?

Bodyweight Triceps Extension (70% of bodyweight).

How we rate exercises: https://seto.fit/guides/methodology/

---
seto — Fast, simple, clever workout tracking — offline-first by design. https://seto.fit/

Video licensed for playback on seto only — copying, downloading, or redistribution is prohibited. https://seto.fit/terms/