TETSU

Butt-Ups vs Sledgehammer Swing

The Butt-Ups and the Sledgehammer Swing both train the abs as their primary muscle. The Butt-Ups are bodyweight-only while the Sledgehammer Swing uses a hammer. Here is how they compare and when to pick each.

Head to head

Side-by-side comparison

Butt-UpsSledgehammer Swing
Primary muscleabsabs
Body partwaistwaist
Supporting muscleship flexors and lower backforearms and shoulders
Equipmentbodyweighthammer
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.

Sledgehammer Swing — first steps

  1. Stand with your feet shoulder-width apart and hold the sledge hammer with both hands.
  2. Engage your core and keep your back straight.

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. 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 Sledgehammer Swing?

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 Sledgehammer Swing offers a different stimulus. Choose based on your equipment and which movement you can progress consistently.

Can I do both the Butt-Ups and the Sledgehammer Swing 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 Sledgehammer Swing 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 forearms and shoulders for the Sledgehammer Swing.

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.