{
  "$schema": "https://openexercise.org/schema/v0/exercise.json",
  "aliases": [
    {
      "text": "Incline Crunch",
      "kind": "common"
    },
    {
      "text": "Decline Bench Crunch",
      "kind": "common"
    },
    {
      "text": "Slant Board Crunch",
      "kind": "common"
    },
    {
      "text": "Decline Ab Crunch",
      "kind": "common"
    },
    {
      "text": "Incline Crunches",
      "kind": "common"
    },
    {
      "text": "Negative Crunches",
      "kind": "common"
    }
  ],
  "anatomy": {
    "muscles": [
      {
        "muscle": "rectus-abdominis",
        "role": "prime-mover"
      },
      {
        "muscle": "obliques",
        "role": "synergist"
      },
      {
        "muscle": "iliopsoas",
        "role": "stabilizer"
      },
      {
        "muscle": "rectus-femoris",
        "role": "stabilizer"
      },
      {
        "muscle": "transversus-abdominis",
        "role": "stabilizer"
      }
    ],
    "joints": [
      {
        "joint": "thoracic-spine",
        "actions": [
          "flexion"
        ]
      },
      {
        "joint": "lumbar-spine",
        "actions": [
          "flexion"
        ]
      },
      {
        "joint": "hip",
        "actions": [
          "isometric-stabilization"
        ]
      }
    ]
  },
  "classification": {
    "modalities": [
      "calisthenics",
      "hypertrophy",
      "strength"
    ],
    "movement_patterns": [
      "spinal-flexion"
    ],
    "mechanics": "isolation",
    "force": "pull",
    "kinetic_chain": "open",
    "laterality": "bilateral",
    "planes": [
      "sagittal"
    ],
    "contraction": [
      "dynamic"
    ],
    "level": "beginner"
  },
  "equipment": {
    "optional": [
      "weight-plate"
    ],
    "required": [
      [
        "adjustable-bench",
        "bench"
      ]
    ]
  },
  "external_ids": {
    "wger": "171,427"
  },
  "id": "oec:decline-crunch",
  "instructions": {
    "setup": [
      "Secure your legs and ankles under the padded rollers at the elevated end of a decline bench.",
      "Lie back on the bench so your head is positioned lower than your hips.",
      "Place your hands lightly beside your ears or cross your arms over your chest without interlocking your fingers behind your head."
    ],
    "steps": [
      "Engage your abdominals and tuck your chin slightly toward your chest.",
      "Curl your upper torso off the bench by flexing your spine and drawing your ribcage down toward your pelvis.",
      "Pause and squeeze your abdominals hard at the peak of the contraction when your shoulder blades clear the bench.",
      "Slowly uncurl your spine under control to lower your torso back down to the starting position."
    ],
    "breathing": "Exhale forcefully as you curl upward against gravity; inhale as you slowly lower your torso back down.",
    "cues": [
      "Ribs to hips",
      "Roll up like a carpet",
      "Do not yank your neck"
    ],
    "common_faults": [
      {
        "fault": "Pulling on the head and neck with the hands.",
        "correction": "Cross arms over the chest or place fingertips lightly by your ears without pulling forward."
      },
      {
        "fault": "Performing a full sit-up by pivoting at the hips rather than curling the spine.",
        "correction": "Keep your lower back in contact with the pad and focus purely on flexing your spine to lift your shoulder blades."
      },
      {
        "fault": "Relying on momentum and bouncing off the bench at the bottom.",
        "correction": "Maintain continuous abdominal tension throughout and control the descent fully."
      }
    ],
    "safety": {
      "precautions": [
        "Ensure your legs are securely locked into the ankle pads before leaning back into the decline position."
      ],
      "spotter": "not-needed"
    }
  },
  "measurement": {
    "load": {
      "kind": "bodyweight"
    },
    "profiles": [
      {
        "required": [
          "reps"
        ],
        "optional": [
          "rpe"
        ]
      }
    ],
    "records": {},
    "reps_counted": "total"
  },
  "name": "Decline Crunch",
  "previous_ids": [
    "oec:incline-crunches",
    "oec:negative-crunches"
  ],
  "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: Incline Crunches",
        "url": "https://wger.de/en/exercise/171/view-base",
        "license": "CC-BY-SA-3.0",
        "author": "wger.de"
      },
      {
        "title": "wger: Negative Crunches",
        "url": "https://wger.de/en/exercise/427/view-base",
        "license": "CC-BY-SA-3.0",
        "author": "wger.de"
      }
    ]
  },
  "relations": [
    {
      "type": "variation-of",
      "target": "oec:crunch"
    },
    {
      "type": "progression-of",
      "target": "oec:crunch"
    },
    {
      "type": "substitute-for",
      "target": "oec:cable-kneeling-crunch"
    },
    {
      "type": "substitute-for",
      "target": "oec:machine-crunch"
    },
    {
      "type": "substitute-for",
      "target": "oec:weighted-crunch"
    },
    {
      "type": "substitute-for",
      "target": "oec:stability-ball-crunch"
    }
  ],
  "setup": {
    "position": "supine",
    "range": "full"
  },
  "status": "active",
  "summary": "An abdominal isolation exercise performed on a decline bench where the torso curls upward against gravity through spinal flexion."
}