{
  "$schema": "https://openexercise.org/schema/v0/exercise.json",
  "aliases": [
    {
      "text": "Seated Corkscrew Crunch",
      "kind": "common"
    },
    {
      "text": "Seated In-and-Out Corkscrew",
      "kind": "common"
    }
  ],
  "anatomy": {
    "muscles": [
      {
        "muscle": "rectus-abdominis",
        "role": "prime-mover"
      },
      {
        "muscle": "obliques",
        "role": "prime-mover"
      },
      {
        "muscle": "iliopsoas",
        "role": "synergist"
      },
      {
        "muscle": "rectus-femoris",
        "role": "synergist"
      },
      {
        "muscle": "transversus-abdominis",
        "role": "stabilizer"
      }
    ],
    "joints": [
      {
        "joint": "lumbar-spine",
        "actions": [
          "flexion",
          "rotation"
        ]
      },
      {
        "joint": "thoracic-spine",
        "actions": [
          "flexion",
          "rotation"
        ]
      },
      {
        "joint": "hip",
        "actions": [
          "flexion",
          "extension"
        ]
      },
      {
        "joint": "knee",
        "actions": [
          "flexion",
          "extension"
        ]
      }
    ]
  },
  "classification": {
    "modalities": [
      "calisthenics"
    ],
    "movement_patterns": [
      "spinal-flexion",
      "rotation"
    ],
    "mechanics": "compound",
    "force": "pull",
    "kinetic_chain": "open",
    "laterality": "alternating",
    "planes": [
      "sagittal",
      "transverse"
    ],
    "contraction": [
      "dynamic"
    ],
    "level": "intermediate"
  },
  "equipment": {
    "optional": [
      "mat"
    ],
    "required": []
  },
  "external_ids": {
    "wger": "1477"
  },
  "id": "oec:seated-corkscrew",
  "instructions": {
    "setup": [
      "Sit on an exercise mat with your knees slightly bent and feet flat on the floor.",
      "Place your hands on the floor slightly behind your hips with fingers pointing forward to support your torso.",
      "Lean back slightly to engage your core and lift your feet a few inches off the floor."
    ],
    "steps": [
      "Pull your knees up and diagonally across toward one shoulder while simultaneously rotating your pelvis and lower torso to that side.",
      "Pause briefly at the peak contraction, squeezing your obliques and abdominal wall.",
      "Extend your legs back out to the center hovering position with control.",
      "Repeat the movement by pulling your knees diagonally across toward the opposite shoulder.",
      "Continue alternating sides for the target repetitions or duration."
    ],
    "breathing": "Exhale forcefully as you tuck and rotate your knees toward your chest; inhale as you extend your legs back out.",
    "cues": [
      "Rotate from the waist, not just the knees.",
      "Keep the chest proud and open.",
      "Control the extension without touching your feet down."
    ],
    "common_faults": [
      {
        "fault": "Relying purely on momentum rather than muscular control.",
        "correction": "Slow down the repetition cadence and pause at full knee flexion to emphasize oblique recruitment."
      },
      {
        "fault": "Collapsing into the shoulders and rounding the upper spine excessively.",
        "correction": "Press firmly through your palms to keep your chest lifted and shoulders depressed."
      },
      {
        "fault": "Hyperextending the lower back during leg extension.",
        "correction": "Maintain abdominal tension and only extend your legs as far as you can control without excessive lumbar arching."
      }
    ],
    "safety": {
      "precautions": [
        "Avoid rapid, uncontrolled twisting if you have a history of lumbar spine disc injuries."
      ],
      "spotter": "not-needed"
    }
  },
  "measurement": {
    "load": {
      "kind": "bodyweight"
    },
    "profiles": [
      {
        "required": [
          "reps"
        ],
        "optional": [
          "rpe"
        ]
      },
      {
        "required": [
          "duration"
        ],
        "optional": [
          "reps",
          "rpe"
        ]
      }
    ],
    "records": {},
    "reps_counted": "total"
  },
  "name": "Seated Corkscrew",
  "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: Seated Corkscrew",
        "url": "https://wger.de/en/exercise/1477/view-base",
        "license": "CC-BY-SA-4.0",
        "author": "Moffi"
      }
    ]
  },
  "relations": [
    {
      "type": "variation-of",
      "target": "oec:seated-knee-tuck"
    },
    {
      "type": "progression-of",
      "target": "oec:seated-knee-tuck"
    },
    {
      "type": "substitute-for",
      "target": "oec:russian-twist"
    }
  ],
  "setup": {
    "position": "seated"
  },
  "status": "active",
  "summary": "A seated bodyweight core exercise that combines hip and spinal flexion with rotation to target the rectus abdominis and obliques."
}