{
  "$schema": "https://openexercise.org/schema/v0/exercise.json",
  "aliases": [
    {
      "text": "Seated Machine Crunch",
      "kind": "common"
    },
    {
      "text": "Machine Ab Crunch",
      "kind": "common"
    },
    {
      "text": "Abdominal Crunch Machine",
      "kind": "common"
    },
    {
      "text": "Crunches on Machine",
      "kind": "common"
    },
    {
      "text": "3008 Klappsitz",
      "kind": "common"
    },
    {
      "text": "3008 Abdominal Crunch",
      "kind": "common"
    }
  ],
  "anatomy": {
    "muscles": [
      {
        "muscle": "rectus-abdominis",
        "role": "prime-mover"
      },
      {
        "muscle": "obliques",
        "role": "synergist"
      },
      {
        "muscle": "iliopsoas",
        "role": "synergist"
      },
      {
        "muscle": "transversus-abdominis",
        "role": "stabilizer"
      }
    ],
    "joints": [
      {
        "joint": "lumbar-spine",
        "actions": [
          "flexion",
          "extension"
        ]
      },
      {
        "joint": "thoracic-spine",
        "actions": [
          "flexion",
          "extension"
        ]
      },
      {
        "joint": "hip",
        "actions": [
          "isometric-stabilization"
        ]
      }
    ]
  },
  "classification": {
    "modalities": [
      "hypertrophy",
      "strength"
    ],
    "movement_patterns": [
      "spinal-flexion"
    ],
    "mechanics": "isolation",
    "force": "push",
    "kinetic_chain": "open",
    "laterality": "bilateral",
    "planes": [
      "sagittal"
    ],
    "contraction": [
      "dynamic"
    ],
    "level": "beginner"
  },
  "equipment": {
    "required": [
      [
        "selectorized-machine",
        "plate-loaded-machine"
      ]
    ]
  },
  "external_ids": {
    "wger": "172,1924"
  },
  "id": "oec:machine-crunch",
  "instructions": {
    "setup": [
      "Adjust the seat height so that your chest rests comfortably against the upper pad and the machine's axis of rotation aligns with your mid-torso.",
      "Sit back firmly into the pad and secure your feet beneath the foot rollers or flat on the footrests.",
      "Grasp the handles lightly to stabilize your upper body without pulling with your arms."
    ],
    "steps": [
      "Initiate the movement by drawing your ribs down toward your pelvis, curling your spine forward through a full contraction.",
      "Pause briefly at the bottom of the movement while actively squeezing your abdominal muscles.",
      "Control the return as your spine slowly uncurls back to an upright position, resisting the stack without letting the weights slam."
    ],
    "breathing": "Exhale forcefully as you crunch forward and empty your lungs to deepen the abdominal contraction, then inhale as you slowly return to the upright position.",
    "cues": [
      "Ribs to pelvis",
      "Curl your spine, do not just hinge at the hips",
      "Hands are hooks, do not pull with your arms"
    ],
    "common_faults": [
      {
        "fault": "Hinging purely at the hips with a rigid, flat spine rather than flexing the trunk.",
        "correction": "Focus on actively curling the spine forward vertebra by vertebra to ensure the rectus abdominis does the work."
      },
      {
        "fault": "Yanking on the handles with the arms to generate momentum.",
        "correction": "Maintain a light, relaxed grip and initiate the motion entirely from your core."
      },
      {
        "fault": "Hyperextending the lower back aggressively at the top of each repetition.",
        "correction": "Stop the return once you reach an upright, neutral seated posture before the lower back overextends."
      }
    ],
    "safety": {
      "precautions": [
        "Avoid using excessive loads that force the neck into severe forward flexion or compromise spinal control."
      ],
      "spotter": "not-needed"
    }
  },
  "measurement": {
    "load": {
      "convention": "weight-stack",
      "implements": 1,
      "kind": "external"
    },
    "profiles": [
      {
        "required": [
          "reps",
          "load"
        ],
        "optional": [
          "rpe"
        ]
      }
    ],
    "records": {
      "volume": true
    },
    "reps_counted": "total"
  },
  "name": "Machine Crunch",
  "previous_ids": [
    "oec:crunches-on-machine",
    "oec:3008-abdominal-crunch"
  ],
  "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: Crunches on Machine",
        "url": "https://wger.de/en/exercise/172/view-base",
        "license": "CC-BY-SA-3.0",
        "author": "wger.de"
      },
      {
        "title": "wger: 3008 Abdominal Crunch",
        "url": "https://wger.de/en/exercise/1924/view-base",
        "license": "CC-BY-SA-4.0"
      }
    ]
  },
  "relations": [
    {
      "type": "variation-of",
      "target": "oec:crunch"
    },
    {
      "type": "substitute-for",
      "target": "oec:cable-kneeling-crunch"
    },
    {
      "type": "substitute-for",
      "target": "oec:weighted-crunch"
    }
  ],
  "setup": {
    "position": "seated",
    "range": "full"
  },
  "status": "active",
  "summary": "A seated machine exercise that loads spinal flexion to strengthen and hypertrophy the abdominal muscles."
}