Fitness · Core

Crunch

Target Abdominals  ·  Equipment Body weight  ·  Level Beginner  ·  Reps 12

Crunch is a beginner-level fitness movement targeting the abdominals, written in Posecode, a small open-source language that capable language models can use to describe human movement as text. Authored joint targets and reach-IK solves are constrained to Posecode's configured per-axis bounds. Those bounds constrain the visualization, but they do not certify that a complete movement is safe or clinically correct. This page documents a code example; it is not exercise instruction.

Movement phases

Phase cues are display-only coaching text. The executable joint and contact directives in the source below determine the animation.

1. Set up0.5s · flow  
2. Curl up1s · settle Curl the shoulders off the floor, ribs toward the hips
3. Lower1.2s · settle Lower the upper back down with control

The .posecode source

This is the exact text used by the linked playground animation: phases and joint angles, not 3D transforms.

posecode exercise "Crunch"
  rig humanoid
  pose start = supine

  step "Set up" 0.5s flow:
    hips: flex 45
    knees: flex 90
    ankles: plantarflex 50
    shoulders: flex 45
    pin: pelvis floor
    reach: feet floor

  step "Curl up" 1s settle:
    hips: flex 45
    knees: flex 90
    ankles: plantarflex 50
    shoulders: flex 45
    spine: flex 30
    chest: flex 20
    neck: flex 15
    pin: pelvis floor
    reach: feet floor
    cue "Curl the shoulders off the floor, ribs toward the hips"

  step "Lower" 1.2s settle:
    hips: flex 45
    knees: flex 90
    ankles: plantarflex 50
    shoulders: flex 45
    spine: flex 0
    chest: flex 0
    neck: flex 0
    pin: pelvis floor
    reach: feet floor
    cue "Lower the upper back down with control"

  repeat 12

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