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Brand new Core

Sit-Up

A classic core builder. Tuck your feet under something stable if they lift.

Sets & reps
3 sets of 10 reps
Type
Isolation (core)
What you need
None (a mat helps)
ShouldersChestAbs / coreObliquesBicepsForearmsQuadsAdductorsCalvesFrontTrapsLatsLower backTricepsForearmsGlutesHamstringsCalvesBack

Muscles worked

  • Abs / core
  • Obliques

Rectus abdominis (abs), obliques, hip flexors

What do these muscles do? →

How to do it

  1. Step 1Lie on your back with your knees bent and feet flat on the floor.
  2. Step 2Place your hands across your chest or lightly behind your head.
  3. Step 3Engage your core and curl your torso up toward your thighs.
  4. Step 4Pause briefly at the top, then lower back down with control.

Watch it done

A demonstration of the sit-up from start to finish.

These videos are external resources found online and are not my own content. Feel free to do your own research as well.

Common mistakes

  • Yanking your neck with your hands.
  • Using momentum to fling yourself up.
  • Letting your feet lift off the floor.

Can't quite do it yet?

Everyone starts somewhere. Try these easier variations until the full movement feels within reach.

  • Crunch — only lift your head and shoulders, not the whole torso.
  • Tuck your feet under a couch or have someone hold them down.
  • Reach your arms forward as you sit up to act as a counterbalance.

Why it's worth doing

  • A straightforward way to strengthen the abs beginners can feel straight away.
  • Pairs well with the plank for a balanced core session.