( 01 ) — Articles · AUG 19, 2026 · 7 MIN
Your core has four jobs. Most ab workouts train one.
Crunches aren't wrong — they're just one quarter of the picture. Sort core work by what the muscles are actually being asked to do and the gaps show up immediately. Here are nine exercises, grouped by job, with the cue that makes each one count.
AB WHEEL — RESIST EXTENSION
( 02 ) — The four jobs
Mostly, the core's job is to stop movement.
Under a heavy bar, on a long carry, on a single leg — your midsection is mostly working to keep your spine still while everything else moves. That's why a set of crunches and a hard plank feel like completely different exercises: they're different jobs.
Four jobs cover almost everything worth training: resist extension, resist rotation, flex, and rotate. Pick one exercise from each and you have a complete core session in about ten minutes.
( 03 ) — Resist extension
Resist extension. Stopping your lower back from arching when something pulls it there.
The job your core does under a heavy squat, a loaded carry, and every plank variation ever invented. Start where you can hold a flat back, then make it harder.
( 04 ) — Resist rotation
Resist rotation. Staying square when a force is trying to twist you.
The least trained and most transferable job — it's what keeps you stable on single-leg work, carries, and every sport that involves changing direction.
( 05 ) — Flex the spine
Flex the spine. Bringing ribs and hips toward each other — the classic ab exercise.
The abs' most obvious job and the one most workouts train exclusively. Worth doing, not worth doing alone.
( 06 ) — Rotate with control
Rotate with control. Producing twist, rather than resisting it.
Rounds out the set. Keep the range honest and the load modest — this is the job where speed and ego cause the most trouble.
( 07 ) — Putting it together
One from each job, twice a week.
A workable default: pick one exercise from each of the four jobs, two or three sets each, tacked onto the end of two training days a week. Holds run 20–40 seconds; reps sit in the 8–15 range. That's ten minutes, and it covers ground most dedicated ab routines miss entirely.
Progress it the same way you progress everything else — a little more than last time: longer holds, more reps, a harder variation, or load added to the rotation work. Core training stalls for exactly the same reason bench presses do, and it responds to exactly the same fix.
Every exercise above links to its page in our library — animation, muscles worked, and equipment. There are 600+ more where these came from.
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