{
  "$schema": "https://openexercise.org/schema/v0/exercise.json",
  "aliases": [
    {
      "text": "Butterfly Superman",
      "kind": "common"
    },
    {
      "text": "Prone Prisoner Back Extension",
      "kind": "common"
    }
  ],
  "anatomy": {
    "muscles": [
      {
        "muscle": "erector-spinae",
        "role": "prime-mover"
      },
      {
        "muscle": "trapezius-middle",
        "role": "synergist"
      },
      {
        "muscle": "trapezius-lower",
        "role": "synergist"
      },
      {
        "muscle": "rhomboids",
        "role": "synergist"
      },
      {
        "muscle": "deltoid-posterior",
        "role": "synergist"
      },
      {
        "muscle": "gluteus-maximus",
        "role": "stabilizer"
      }
    ],
    "joints": [
      {
        "joint": "thoracic-spine",
        "actions": [
          "extension"
        ]
      },
      {
        "joint": "lumbar-spine",
        "actions": [
          "extension"
        ]
      },
      {
        "joint": "scapulothoracic",
        "actions": [
          "retraction"
        ]
      },
      {
        "joint": "glenohumeral",
        "actions": [
          "horizontal-abduction",
          "external-rotation"
        ]
      },
      {
        "joint": "cervical-spine",
        "actions": [
          "isometric-stabilization"
        ]
      }
    ]
  },
  "classification": {
    "modalities": [
      "calisthenics"
    ],
    "movement_patterns": [
      "spinal-extension"
    ],
    "mechanics": "compound",
    "force": "pull",
    "kinetic_chain": "open",
    "laterality": "bilateral",
    "planes": [
      "sagittal"
    ],
    "contraction": [
      "dynamic"
    ],
    "level": "beginner"
  },
  "equipment": {
    "optional": [
      "mat"
    ],
    "required": []
  },
  "external_ids": {
    "wger": "1908"
  },
  "id": "oec:prisoner-superman",
  "instructions": {
    "setup": [
      "Lie face down on a mat with your legs extended straight behind you.",
      "Place your hands behind your head with fingers lightly touching or interlaced, pointing your elbows out wide to the sides."
    ],
    "steps": [
      "Engage your glutes and core to anchor your lower body against the floor.",
      "Contract your spinal erectors and upper back to lift your chest and upper ribs off the floor.",
      "Simultaneously draw your elbows upward toward the ceiling, actively retracting your shoulder blades.",
      "Hold the contraction at the top for a brief pause while keeping your neck neutral.",
      "Lower your chest and upper body slowly back to the starting position."
    ],
    "breathing": "Exhale as you raise your chest and elbows off the floor; inhale as you lower with control.",
    "cues": [
      "Lead with the chest, not the chin",
      "Pull elbows toward the ceiling",
      "Keep eyes focused down at the mat"
    ],
    "common_faults": [
      {
        "fault": "Pulling on the back of the neck with the hands, causing excessive cervical flexion or strain.",
        "correction": "Rest fingertips lightly against the temples or occiput without pulling on the head."
      },
      {
        "fault": "Hyperextending the neck by looking straight ahead or upward.",
        "correction": "Maintain a packed neck and keep your gaze directed at the floor throughout the repetition."
      }
    ],
    "safety": {
      "precautions": [
        "Avoid forceful spinal hyperextension if experiencing acute lower back irritation."
      ],
      "spotter": "not-needed"
    }
  },
  "measurement": {
    "duration_counted": "total",
    "load": {
      "convention": "not-applicable",
      "kind": "bodyweight"
    },
    "profiles": [
      {
        "required": [
          "reps"
        ],
        "optional": [
          "rpe"
        ]
      },
      {
        "required": [
          "duration"
        ],
        "optional": [
          "rpe"
        ]
      }
    ],
    "records": {},
    "reps_counted": "total"
  },
  "name": "Prisoner Superman",
  "previous_ids": [
    "oec:butterfly-superman"
  ],
  "provenance": {
    "generated": [
      "/name",
      "/summary",
      "/classification",
      "/anatomy",
      "/equipment",
      "/measurement",
      "/instructions",
      "/setup",
      "/relations"
    ],
    "license": "CC-BY-SA-4.0",
    "review": {
      "status": "machine-generated",
      "model": "gemini-3.8-flash",
      "at": "2026-10-31"
    },
    "sources": [
      {
        "title": "wger: Butterfly Superman",
        "url": "https://wger.de/en/exercise/1908/view-base",
        "license": "CC-BY-SA-4.0",
        "author": "cybro"
      }
    ]
  },
  "relations": [
    {
      "type": "variation-of",
      "target": "oec:superman"
    },
    {
      "type": "substitute-for",
      "target": "oec:superman"
    }
  ],
  "setup": {
    "position": "prone",
    "stance": {
      "kind": "parallel"
    }
  },
  "status": "active",
  "summary": "A bodyweight prone back extension performed with hands behind the head to strengthen the erector spinae, rhomboids, and lower trapezius."
}