Dead Bug

What is the Dead Bug?

The dead bug is a beginner-friendly, back-safe anti-extension drill performed on your back: you lower an opposite arm and leg toward the floor while keeping your lower back pressed flat. It teaches the core to resist extension and stay braced while the limbs move, which is the foundation for harder ab work.

Muscles worked

Primary: Abs

The rectus abdominis and deep transverse abdominis brace to keep the lower back flat against the floor as the extending arm and leg try to pull the spine into an arch.

Stabilizers

The opposite-side trunk works to resist any twist, keeping the pelvis level while a single arm and leg lower.

How to perform the Dead Bug

1. Lie on your back with arms reaching straight up toward the ceiling and hips and knees bent to ninety degrees in a tabletop.
2. The entire point of the dead bug is to keep the spine perfectly still while the limbs move. It is anti-extension, not a crunch.
3. Press the lower back flat into the floor and brace the abs, then hold that trunk position as the reference for every rep.
4. Slowly extend the opposite arm and leg away from you, lowering them toward the floor while the lower back stays glued down.
5. Reach only as far as you can before the lumbar would arch off the floor. That arch is the exact failure you are training against.
6. Return the limbs to the start under control and repeat on the other side, keeping the pelvis and ribcage motionless throughout.

Suggested working range: 12–20 reps. Default progression: double progression.

Mechanics

An anti-extension coordination drill: as one arm and the opposite leg reach away, the levers try to hyperextend and rotate the spine, and the abs fire to hold the lower back flat and the pelvis still. The limbs move but the trunk deliberately doesn’t. The training effect is in resisting that motion, done slowly and under control.

Form cues

• •Press the lower back into the floor before you move and keep it there. If it arches as the limbs lower, you’ve gone too far.
• •Move the opposite arm and leg slowly and together, then return under control rather than dropping them.
• •Exhale as you extend the limbs to help lock in the brace and keep the ribs down.

Common mistakes

• •Letting the lower back arch off the floor as the arm and leg extend, which is the exact fault the drill trains against.
• •Rushing the limbs out and back with momentum instead of moving slowly around a still spine.
• •Holding the breath and losing the brace so the ribcage flares as the limbs reach.
• •Reaching the leg so far and low that the pelvis tips and the lumbar pops up.

Variations & alternatives

• •Hollow body hold: the static, both-limbs-at-once progression of the same flat-back brace.
• •Plank: a face-down anti-extension hold that reinforces trunk bracing.
• •Ab wheel rollout: an advanced moving anti-extension movement to progress toward.

Crunch

Abs · Bodyweight

Cable Crunch

Abs · Cable

Hanging Leg Raise

Abs · Bodyweight

Machine Crunch

Abs · Machine

Decline Crunch

Abs · Bodyweight

Programming: sets, reps & when to use it

Program dead bugs for controlled reps, about 12–20 per side, as a warm-up primer or low-fatigue core work. Because it’s back-safe and beginner-friendly, it’s ideal for grooving the brace before loading heavier ab movements. Quality of control beats rep count.

Frequently asked questions