{
  "$schema": "https://openexercise.org/schema/v0/exercise.json",
  "aliases": [
    {
      "text": "pelvic tilt 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"
        ]
      },
      {
        "joint": "hip",
        "actions": [
          "flexion"
        ]
      }
    ]
  },
  "classification": {
    "modalities": [
      "calisthenics",
      "hypertrophy"
    ],
    "movement_patterns": [
      "spinal-flexion"
    ],
    "mechanics": "isolation",
    "force": "pull",
    "kinetic_chain": "open",
    "laterality": "bilateral",
    "planes": [
      "sagittal"
    ],
    "contraction": [
      "dynamic"
    ],
    "level": "beginner"
  },
  "equipment": {
    "optional": [
      "mat"
    ],
    "required": []
  },
  "external_ids": {
    "wger": "1772"
  },
  "id": "oec:reverse-crunch",
  "instructions": {
    "setup": [
      "Lie flat on your back on a mat with your arms resting at your sides, palms pressed into the floor.",
      "Bend your knees to approximately 90 degrees and lift your feet slightly off the floor."
    ],
    "steps": [
      "Contract your abdominals to curl your pelvis off the floor, bringing your knees toward your chest.",
      "Pause for a brief contraction at the top as your lower back lifts off the floor.",
      "Lower your pelvis back to the starting position in a slow, controlled manner without letting your lower back arch off the mat."
    ],
    "breathing": "Exhale as you curl your hips toward your chest; inhale as you slowly return to the starting position.",
    "cues": [
      "Roll your pelvis toward your ribs",
      "Control the descent",
      "Don't swing your legs"
    ],
    "common_faults": [
      {
        "fault": "Swinging the legs to generate momentum rather than curling the pelvis.",
        "correction": "Keep your knee angle fixed and focus entirely on posterior pelvic tilt and rolling the hips up."
      },
      {
        "fault": "Allowing the lumbar spine to hyperextend at the bottom of the movement.",
        "correction": "Stop the descent before your lower back peels off the floor and maintain core engagement throughout."
      }
    ],
    "safety": {
      "spotter": "not-needed"
    }
  },
  "measurement": {
    "load": {
      "kind": "bodyweight"
    },
    "profiles": [
      {
        "required": [
          "reps"
        ],
        "optional": [
          "rpe"
        ]
      }
    ],
    "records": {},
    "reps_counted": "total"
  },
  "name": "Reverse 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: Reverse crunch",
        "url": "https://wger.de/en/exercise/1772/view-base",
        "license": "CC-BY-SA-4.0",
        "author": "eufvksruh"
      }
    ]
  },
  "relations": [
    {
      "type": "variation-of",
      "target": "oec:crunch"
    },
    {
      "type": "regression-of",
      "target": "oec:captain-s-chair-knee-raise"
    },
    {
      "type": "regression-of",
      "target": "oec:hanging-knee-raise"
    },
    {
      "type": "substitute-for",
      "target": "oec:captain-s-chair-knee-raise"
    }
  ],
  "setup": {
    "position": "supine"
  },
  "status": "active",
  "summary": "A supine bodyweight core exercise where the pelvis is curled off the floor toward the ribs to target the abdominals."
}