TETSU3/4 Sit-Up vs Pull-In (On Stability Ball)
The 3/4 Sit-Up and the Pull-In (On Stability Ball) both train the abs as their primary muscle. The 3/4 Sit-Up is bodyweight-only while the Pull-In (On Stability Ball) uses a stability ball. Here is how they compare and when to pick each.
Side-by-side comparison
| 3/4 Sit-Up | Pull-In (On Stability Ball) | |
|---|---|---|
| Primary muscle | abs | abs |
| Body part | waist | waist |
| Supporting muscles | hip flexors and lower back | hip flexors |
| Equipment | bodyweight | stability ball |
| Steps in our guide | 5 | 5 |
How each one starts
3/4 Sit-Up — first steps
- Lie flat on your back with your knees bent and feet flat on the ground.
- Place your hands behind your head with your elbows pointing outwards.
Pull-In (On Stability Ball) — first steps
- Start by sitting on the stability ball with your feet flat on the ground and your knees bent at a 90-degree angle.
- Place your hands on the sides of the stability ball for support.
Full step-by-step guides are linked below.
Which should you choose?
The 3/4 Sit-Up needs no equipment and scales 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.
Full form guides
Common questions
Is the 3/4 Sit-Up better than the Pull-In (On Stability Ball)?
Neither is universally better — both train the abs as the primary mover. The 3/4 Sit-Up needs no equipment and scales 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 3/4 Sit-Up 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 3/4 Sit-Up 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 3/4 Sit-Up 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.