Butterfly Sit-ups

How to do it

Lie supine, bring the soles of your feet together, and let your knees fall open. Touch the floor behind your head, then sit all the way up and touch your toes.

The coaching cue

"Roll up one vertebra at a time."

What changes inside an AMRAP

The butterfly leg position mechanically disables the hip flexors, forcing pure abdominal contraction. Do not use your arms to swing forward.

Common mistakes

• Letting the knees rise off the floor to help the torso up.
• Reaching for the shins rather than all the way to the toes.

Workouts that use butterfly sit-ups

• Core Melt

  5 minute AMRAP — 10 V-Ups, 15 Butterfly Sit-ups, 15s Hollow Hold

• The Apex

  15 minute AMRAP — 20 Glute Bridges, 10 Dive-Bomber Push-ups, 20 Butterfly Sit-ups

• The Long Slog

  20 minute AMRAP — 10 Hand-Release Push-ups, 20 Walking Lunges, 15 Butterfly Sit-ups, 30 Mountain Climbers

• Shockwave

  20 minute AMRAP — 15 Down-Ups, 10 Diamond Push-ups, 15 Fast Calf Raises, 15 Butterfly Sit-ups

Run one with your friends

Every workout above runs on a shared countdown — one clock for the whole crew, one leaderboard, wherever everyone is training.