ProgreviaDead bug: proper form, muscles worked and common mistakes
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How to do it
On your back, arms to the ceiling and hips and knees at 90°, extend one arm and the opposite leg together without letting the lower back lift off the floor. Alternate slowly. Anti-extension core work.
Muscles worked
Main muscle: abs. When it plans weekly volume, every set of this exercise counts in full for abs: the generator does not split it with other muscles.
Dead bug: the ab exercise where the torso stays still and the limbs move
The dead bug flips the logic of the reverse crunch. In the reverse crunch the pelvis curls and the spine flexes; in the dead bug the spine does not move at all and the only thing that changes is where your arms and legs are. The entire challenge is keeping your lower back from lifting off the floor while the lever of one arm and the opposite leg moves away. That makes it an exercise about control rather than fatigue, so you can do it often because recovery costs little.
It works well as a warm-up before squats or deadlifts to practice bracing, and for beginners who cannot feel their core during crunches yet. If your neck gets loaded in flexion exercises, this one sidesteps that. If your lower back lifts when the leg extends, shorten the movement and do not lower the heel as far.
Progress by lengthening the lever gradually: lower the foot closer to the floor, extend both legs while alternating arms, or hold a light weight or a band in your hands. Time your exhale to the reach, since breathing out helps keep the ribs down. Once this is solid, the Hollow hold is the natural next step.
Technical sheet
- Movement pattern
- Core
- Minimum level
- Beginner
- Technical demand
- Basic
- Fatigue it generates
- Low (0.3 out of 2.2)
- Risk if technique breaks down
- Low
These are the values the generator uses to decide where the exercise goes within the session.
Recommended sets and reps
As an isolation exercise, it works best in 3–4 sets of 10–15 reps with 0–2 RIR. Use it at the end of the session to add volume without systemic fatigue.
Common mistakes to avoid
- Letting your lower back lift off the floor as you extend your limbs: shorten the range until it stays down.
- Sticking with the same version once you can do more than 20 reps: move to a harder variation or add load.
- Doing reps too fast, without controlling the eccentric (lowering) phase.
What the research says
As an isolation move, it is mostly a way to add volume to one muscle. Gentil and colleagues (2013) found that, in beginners, adding it to a multi-joint exercise gave no extra arm growth; it pays off later on, or for muscles the compounds barely reach.
On how hard to push: the meta-analysis by Refalo and colleagues (2023) found no clear advantage in going to failure over stopping just short of it. That is why the generator programs it with reps in reserve (RIR) instead of asking for failure on every set.
- Gentil P, Soares SR, Pereira MC, et al. Effect of adding single-joint exercises to a multi-joint exercise resistance-training program on strength and hypertrophy in untrained subjects. Applied Physiology, Nutrition, and Metabolism. 2013;38(3):341-344.
- Refalo MC, Helms ER, Trexler ET, Hamilton DL, Fyfe JJ. Influence of resistance training proximity-to-failure on skeletal muscle hypertrophy: a systematic review with meta-analysis. Sports Medicine. 2023;53(3):649-665.
How Dead bug compares with other abs exercises
Of the 14 abs exercises in the catalogue, ranked from least to most fatiguing by the values the generator uses, Dead bug is number 1 (tied with one other).
That makes it a good candidate for adding abs sets at the end of a session or in heavy weeks, when you want volume without extra fatigue.
With different equipment, the same movement pattern offers 3 alternatives, such as Cable crunch, Pallof press and Landmine rotation.
| Exercise | Equipment | Fatigue | Technique |
|---|---|---|---|
| Reverse crunch | bodyweight | Low (0.3 out of 2.2) | Basic |
| Dead bug | bodyweight | Low (0.3 out of 2.2) | Basic |
| Bicycle crunch | bodyweight | Low (0.4 out of 2.2) | Basic |
| Cable crunch | cable | Low (0.4 out of 2.2) | Basic |
| Pallof press | cable | Low (0.4 out of 2.2) | Needs coaching |
| Plank | bodyweight | Low (0.4 out of 2.2) | Basic |
| Side plank | bodyweight | Low (0.4 out of 2.2) | Basic |
| Hollow hold | bodyweight | Low (0.5 out of 2.2) | Needs coaching |
Bodyweight. In the trial by Kotarsky et al. (2018), four weeks of progressively harder push-ups significantly improved bench press 1RM, just like training the bench press itself. It is a strength result, not a hypertrophy one, and the condition is the word progressive: the exercise has to keep getting harder.
An isolation exercise. In the trial by Gentil et al. (2015), with untrained young men over ten weeks, the biceps curl and the lat pulldown were equally effective for gaining strength and size in the elbow flexors: isolation is not filler.
- Kotarsky CJ, Christensen BK, Miller JS, Hackney KJ. Effect of progressive calisthenic push-up training on muscle strength and thickness. Journal of Strength and Conditioning Research. 2018;32(3):651-659.
- Gentil P, Soares S, Bottaro M. Single vs. multi-joint resistance exercises: effects on muscle strength and hypertrophy. Asian Journal of Sports Medicine. 2015;6(2):e24057.
Related guide
How to get visible abs: the truth about the six-pack
Alternative exercises
More core exercises
Add it to your routine
Progrevia can generate a personalized routine that includes Dead bug based on your level, goal and available days.
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Generate a full routine with the emphasis on abs and Dead bug among your preferred exercises. Free, no sign-up.
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Frequently asked questions
What muscles does Dead bug work?
Dead bug mainly works the abs muscle group, plus synergist and stabilizer muscles depending on the variation.
How many sets of Dead bug should I do?
Between 3 and 5 sets per session, adjusting the total weekly volume for abs to your level (about 10–20 sets per muscle per week).
How can I tell if my lower back is peeling off the floor during a dead bug?
Slide a flat hand under your lower back: if it gets crushed or, on the contrary, the gap keeps growing as you extend the arm and leg, you have lost position. Filming yourself from the side also works. The clearest sign is needing to arch to reach farther, so shorten the range until you can avoid that.
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