To do a dead bug safely over 40, lie on your back with your arms pointing at the ceiling and your knees bent at 90 degrees over your hips. Press your lower back gently toward the floor, breathe out, and slowly lower your opposite arm and leg toward the floor without letting your back arch. Bring them back and switch sides. The rule that makes it work: the moment your back starts to lift, you’ve gone too far.
Why it beats another set of crunches
Your abs’ main job in daily life is to hold your trunk still while your arms and legs do something: carrying groceries, shovelling the driveway, swinging a golf club. The dead bug trains exactly that, lying down, with no load on the spine. It’s one of the safest core exercises for men with a history of back trouble.
It’s also humbling. Done slowly with a full exhale, five reps a side can make your abs shake.
Getting set on the floor
Lie on a mat. Lift your arms straight up so your hands are over your shoulders. Lift your legs so your hips and knees are both bent at 90 degrees, shins parallel to the floor. Breathe out fully and feel your ribs drop and your lower back settle toward the mat. Hold that position the whole time.
Steps
- Take a breath in without letting your ribs flare up.
- As you exhale slowly, reach your right arm back past your head and straighten your left leg toward the floor.
- Lower them only as far as your back stays down. The heel hovers a few centimetres off the floor at full range.
- Pause for a second at the end, still exhaling.
- Return both limbs to the start.
- Repeat with the left arm and right leg. That’s one rep per side.
Faults to fix
The back arch. As the leg drops, the lower back lifts off the floor. Shorten the range, bend the moving knee, or lower only the leg and keep the arms still.
Rushing. Fast reps use momentum instead of control. Count three seconds out and three back.
Holding your breath. Breathing out as you extend is what switches the deep abs on. If you can’t breathe, it’s too hard.
Neck straining. The head lifts to watch the limbs. Keep your head down and relaxed on the mat.
Sets and reps
| Level | Version | Sets × reps per side |
|---|---|---|
| Starting out | Legs only, arms still | 2–3 × 5 |
| Standard | Opposite arm and leg | 3 × 6–8 |
| Stronger | Holding a light dumbbell or with a band pulling the arms | 3 × 6 |
| Advanced | Long-lever with straight legs, slow tempo | 3 × 5 |
Rest 30 to 60 seconds between sets. This is a quality exercise; stop the set when the reps get sloppy.
Easier and harder variations
- Easier: heel taps (lower one bent leg until the heel taps the floor), or same-side arm and leg only.
- Harder: hold a light weight overhead with straight arms, press against a band, or extend both legs together with a flat back.
- Sore lower back: this is already a back-friendly exercise. Keep the range small and the breath long.
- Sore shoulders: keep your arms still at the ceiling and move only the legs.
The bird dog trains the same idea on hands and knees, and the Pallof press adds resistance to twisting. Together with the side plank, they make a complete back-friendly core routine.
Workouts that include it
The dead bug features in the core workout, the mobility routine and the lower back friendly workout. For a weekly plan that puts core work in the right place around your lifts, see the DIY programs.
Questions people also ask
What does the dead bug exercise work?
The deep abdominal muscles and the obliques, which keep your pelvis and lower back steady while your arms and legs move. It trains control more than size.
Should my lower back be flat on the floor?
Gently pressed toward it, yes. You should feel light contact. If the arch returns as your leg lowers, that's the end of your range for now.
Is the dead bug better than crunches?
It trains a different job. Crunches bend the spine; the dead bug teaches your abs to stop the spine moving, which is closer to what they do when you lift, carry or run.
How slow should I go?
Slow enough to breathe out fully as the limbs extend. Three or four seconds out, a short pause, and back is a good rhythm.