Dead Bug
The dead bug looks silly and feels humbling. Lying on your back with arms and knees up, you lower one arm and the opposite leg while your abs keep your lower back pressed into the floor. It trains your trunk to stay quiet while your limbs move, which is exactly what your spine wants during running, lifting, and long days on your feet. Great for beginners and for anyone whose lower back complains during ab work.
Why it works
Most ab exercises make you move your spine. The dead bug makes you refuse to: as your arm and leg drift away, their weight tries to pull your lower back into an arch, and your abdominals fight to keep it flat. That fight is the rep. Because you're lying down with the floor giving you instant feedback, you can feel the exact moment control slips, something a plank never tells you as clearly.
Set up
- Lie on your back on a mat with your knees bent and feet flat.
- Lift your knees over your hips, shins parallel to the floor, like your feet are resting on an invisible chair.
- Reach both arms straight up toward the ceiling.
- Press your lower back gently into the floor and keep that contact for the whole set.
How to do it
- Lower your right arm back toward the floor behind your head while your left leg stretches out long and low.
- Stop just before your arm and heel touch the floor, keeping your lower back pressed down.
- Pause for one breath in that long position.
- Bring the arm and leg back to the start with control.
- Repeat with the left arm and right leg, and keep alternating sides.
- If your lower back peels off the floor, shorten the range and slow down.
Form cues
- Lower back stays welded to the floor.
- Opposite arm, opposite leg.
- Move slow enough to feel the abs shake.
- Ribs down, not flared toward the ceiling.
Breathing: Exhale slowly as the arm and leg lower, inhale as they return; the long exhale is what keeps your ribs down.
Common mistakes
The lower back arches off the floor as the leg extends.
Fix: Don't lower the leg as far. Range you can't control isn't range yet; keep the heel higher and earn the last inches over a few weeks.
Rushing through reps like a bicycle crunch.
Fix: This is a slow-motion exercise. Count three seconds out, pause, three seconds back, and it becomes a completely different movement.
Moving the same-side arm and leg together.
Fix: Pair opposites: right arm with left leg. The cross pattern is what forces your trunk to resist twisting.
Holding your breath for the whole set.
Fix: Match one slow exhale to each rep; breath held is tension your abs aren't producing.
How to program it
- Start with 2 or 3 sets of 6 to 10 reps per side, moving slowly, two or three days a week.
- It shines early in a session as core activation before squats or deadlifts, or bundled into ab work at the end.
- Progress by slowing down and pausing longer before adding anything else; a 5-second rep is harder than 10 fast ones.
- Pairs naturally with the plank and side bridge for a complete no-equipment core trio.
Safety notes
- You should feel work in the front of your abs, not pain in your lower back; if the back complains, shorten the range immediately.
- Keep your head resting on the mat, not craned forward, so your neck stays out of the exercise.
Exercise profile
- Force
- Pull
- Mechanics
- Compound
- Category
- Strength
Frequently asked questions
How many dead bugs should I do?
Six to ten slow reps per side, for 2 or 3 sets, is a solid dose. If you can do 15 per side without your lower back moving, you're ready to slow down further or progress the movement.
Dead bug vs plank: which is better for abs?
They're teammates, not rivals. The plank trains a still hold, the dead bug trains staying still while your limbs move. The dead bug is friendlier for people whose lower backs or wrists dislike planks; the plank takes less coordination. Most core routines benefit from both.
Why is the dead bug so hard for me?
Usually it's the coordination, not weakness. Pairing the opposite arm and leg while breathing slowly takes practice. Start by moving only the legs with your arms held still, then add the arms after a week or two.
Is the dead bug safe if my lower back gets sore easily?
It's one of the most back-friendly ab exercises because your spine stays supported on the floor and never bends. Keep the range small enough that your back stays in contact with the mat, and stop if anything sharp shows up.