TETSU3/4 Sit-Up vs Kettlebell Figure 8
The 3/4 Sit-Up and the Kettlebell Figure 8 both train the abs as their primary muscle. The 3/4 Sit-Up is bodyweight-only while the Kettlebell Figure 8 uses a kettlebell. Here is how they compare and when to pick each.
Side-by-side comparison
| 3/4 Sit-Up | Kettlebell Figure 8 | |
|---|---|---|
| Primary muscle | abs | abs |
| Body part | waist | waist |
| Supporting muscles | hip flexors and lower back | shoulders and forearms |
| Equipment | bodyweight | kettlebell |
| Steps in our guide | 5 | 7 |
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.
Kettlebell Figure 8 — first steps
- Stand with your feet shoulder-width apart, holding a kettlebell in one hand.
- Bend your knees slightly and hinge forward at the hips, keeping your back straight.
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 Kettlebell Figure 8 shifts the load off-center, adding grip and stabilizer 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 Kettlebell Figure 8?
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 Kettlebell Figure 8 shifts the load off-center, adding grip and stabilizer demand. Choose based on your equipment and which movement you can progress consistently.
Can I do both the 3/4 Sit-Up and the Kettlebell Figure 8 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 Kettlebell Figure 8 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 shoulders and forearms for the Kettlebell Figure 8.
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.