TETSU

Butt-Ups vs Pull-In (On Stability Ball)

The Butt-Ups and the Pull-In (On Stability Ball) both train the abs as their primary muscle. The Butt-Ups are bodyweight-only while the Pull-In (On Stability Ball) uses a stability ball. Here is how they compare and when to pick each.

Head to head

Side-by-side comparison

Butt-UpsPull-In (On Stability Ball)
Primary muscleabsabs
Body partwaistwaist
Supporting muscleship flexors and lower backhip flexors
Equipmentbodyweightstability ball
Steps in our guide65
Setup

How each one starts

Butt-Ups — first steps

  1. Lie flat on your back with your knees bent and feet flat on the ground.
  2. Place your hands by your sides, palms facing down.

Pull-In (On Stability Ball) — first steps

  1. Start by sitting on the stability ball with your feet flat on the ground and your knees bent at a 90-degree angle.
  2. Place your hands on the sides of the stability ball for support.

Full step-by-step guides are linked below.

Decision

Which should you choose?

The Butt-Ups need no equipment and scale through leverage, tempo and reps. The Pull-In (On Stability Ball) adds an unstable surface that raises core demand. If your gym has both options, neither is a wrong choice: pick the one that feels strongest through a full range, and swap after 6 to 8 weeks to keep the abs adapting.

Guides

Full form guides

Answers

Common questions

Are the Butt-Ups better than the Pull-In (On Stability Ball)?

Neither is universally better — both train the abs as the primary mover. The Butt-Ups need no equipment and scale through leverage, tempo and reps, while the Pull-In (On Stability Ball) adds an unstable surface that raises core demand. Choose based on your equipment and which movement you can progress consistently.

Can I do both the Butt-Ups and the Pull-In (On Stability Ball) in the same program?

Yes, but usually not in the same session — they overlap heavily on the abs. A common setup is one as your main movement and the other on a second training day, or alternating them block by block.

Do the Butt-Ups and the Pull-In (On Stability Ball) work the same muscles?

The primary muscle is the same: the abs. Supporting muscles differ slightly — hip flexors and lower back for the Butt-Ups versus hip flexors for the Pull-In (On Stability Ball).

Track it in Tetsu

Tetsu tracks both movements separately, keeps your PRs per exercise, and tells you which one is actually progressing. Free to start.