Why does my lower back arch during dead bugs?

Your core is not strong enough to resist the leverage created by your extended limbs, or you are extending them too far from your body. Reduce the range of motion by keeping your arm and leg closer to your torso until you build sufficient strength to maintain a flat back.

Should I touch the floor with my arm and leg during dead bugs?

No, your limbs should hover just above the floor rather than resting on it. Maintaining this hover position keeps constant tension on your core throughout the set.

How do I make dead bugs harder?

Slow down the tempo to increase time under tension, or hold a light weight in your hands to increase the lever arm. You can also pause for 2 to 3 seconds at the bottom position of each repetition to eliminate momentum.

Dead Bug

The dead bug is a core stability exercise performed lying supine while extending opposite limbs in a controlled manner. It suits lifters of all levels who want to build anti-extension core strength and improve coordination between the upper and lower body.

Muscle group: Core
Primary muscles: abs
Equipment: Bodyweight

How to do the Dead Bug

Lie on your back with arms extended straight up toward the ceiling and knees bent at 90 degrees with shins parallel to the floor.
Press your lower back flat into the floor and engage your core to eliminate any arch in your lumbar spine.
Slowly lower your right arm overhead while simultaneously extending your left leg until both are hovering just above the floor.
Return your right arm and left leg to the starting position with control.
Repeat the movement with your left arm and right leg, alternating sides for the prescribed duration.

Form tips

Exhale as you extend your limbs and focus on keeping your ribcage down to prevent your lower back from arching off the floor.
Move slowly and stop the range of motion before your lower back loses contact with the floor.
Keep your extended arm and leg as straight as possible while maintaining tension in your core throughout the entire movement.

Common mistakes

Allowing the lower back to arch off the floor: this shifts tension away from the abs and can strain the lumbar spine.
Moving too quickly through the repetitions: this reduces time under tension and allows momentum to replace muscular control.
Holding your breath during the movement: this creates false stability through intra-abdominal pressure rather than developing true core strength.

Sets and reps

Perform 3 to 4 sets of 30 to 60 seconds for core endurance, or 3 sets of 6 to 10 controlled repetitions per side for strength development.

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Frequently asked questions

Why does my lower back arch during dead bugs?: Your core is not strong enough to resist the leverage created by your extended limbs, or you are extending them too far from your body. Reduce the range of motion by keeping your arm and leg closer to your torso until you build sufficient strength to maintain a flat back.
Should I touch the floor with my arm and leg during dead bugs?: No, your limbs should hover just above the floor rather than resting on it. Maintaining this hover position keeps constant tension on your core throughout the set.
How do I make dead bugs harder?: Slow down the tempo to increase time under tension, or hold a light weight in your hands to increase the lever arm. You can also pause for 2 to 3 seconds at the bottom position of each repetition to eliminate momentum.

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