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Butterfly Crunches (Advanced)

The advanced butterfly crunch keeps the diamond leg position and raises the price: arms extended overhead, a longer curl, and a reach through toward the feet on every rep. The extra lever length turns a beginner staple into a genuinely hard rectus abdominis exercise with no equipment involved. Coached by Maddy (NASM-CPT) — these are the exact form cues he gives on every client's first week.

Muscles worked

Abs · rectus abdominis Obliques

Sets & reps by goal

GoalSets × RepsRest
Strength3 × 3–6 (paused reach)90 s
Muscle3 × 9–1260 s
Endurance2 × 18–2745–60 s

Rep ranges per Helms 2014 · Schoenfeld 2016.

Level — Advanced

A legitimate advanced floor exercise — graduate here after standard butterfly crunches exceed 15 clean reps.

Proper form — 5 cues

  1. Set the butterfly legs, then extend both arms overhead flat along the floor.
  2. Lead the curl with your hands sweeping up and over toward your feet.
  3. Reach through the gap between your knees at the top of each rep.
  4. Hold the reach for a beat with the shoulder blades fully clear of the floor.
  5. Return the arms overhead slowly, keeping them hovering, not resting.

Breathing: Exhale on the reach through the knees, inhale as the arms float back overhead.

The 3 mistakes Maddy corrects most

Throwing the arms to generate swing. The arm-fling creates momentum that carries the torso up — effort without stimulus. Fix: Move the arms and torso as one piece at one speed; the arms are levers, not launchers.
Resting the arms on the floor between reps. Each rest breaks the tension the hovering start position exists to create. Fix: Keep hands a few centimetres off the floor overhead; shorten the set if you cannot.
Knees squeezing together as fatigue builds. The legs creeping up re-invites the hip flexors and unravels the isolation. Fix: Check the diamond shape between reps — soles together, knees wide, legs heavy.

Common questions

What makes the overhead-arm version harder?

Leverage. With the arms extended past your head, the mass your abs must curl sits further from the pivot, so every degree of trunk flexion costs more force. It is the same principle as holding a weight — except the load is your own arms, which makes it free and infinitely available. Expect roughly half your usual crunch reps at first.

Can I add a weight to make it harder still?

Yes — once 15 strict reps of this version feel manageable, hold a small plate or dumbbell in the extended hands and keep everything else identical. Weight in hands overhead is a big jump, so start lighter than pride suggests. The pause at the top and the slow lower remain the quality gates at any load.

Why do I feel this in my upper abs mostly?

Curling the ribcage toward the pelvis is the upper region of the rectus abdominis doing its primary job, so that is where the burn concentrates — that is anatomy working as designed, not a flaw. For the lower region, pair this with leg-raise patterns that move the pelvis instead of the ribs. Complete ab training needs both directions.

Related exercises

Easier: Butterfly Crunches

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