{
  "$schema": "https://openexercise.org/schema/v0/exercise.json",
  "aliases": [
    {
      "text": "Splinter Sit-ups",
      "kind": "misspelling"
    },
    {
      "text": "Sprinter Crunch",
      "kind": "common"
    },
    {
      "text": "Runner's Sit-Up",
      "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"
        ]
      },
      {
        "joint": "knee",
        "actions": [
          "flexion"
        ]
      }
    ]
  },
  "classification": {
    "modalities": [
      "calisthenics",
      "conditioning"
    ],
    "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": "607"
  },
  "id": "oec:sprinter-sit-up",
  "instructions": {
    "setup": [
      "Lie flat on your back on an exercise mat with legs extended straight.",
      "Bend your elbows to 90 degrees with your forearms pointing upward, mimicking a running arm carriage."
    ],
    "steps": [
      "Brace your core and forcefully sit up, rolling through your spine.",
      "Simultaneously drive one knee toward your chest while driving the opposite elbow forward, mimicking a sprinter's stride.",
      "Pause momentarily at the top with your chest tall and core fully engaged.",
      "Lower your torso and leg under control back to the starting position.",
      "Immediately repeat the movement on the opposite side, alternating sides with each repetition."
    ],
    "breathing": "Exhale forcefully as you sit up and drive the knee, and inhale smoothly as you lower back down.",
    "cues": [
      "Drive the opposite knee and elbow together.",
      "Roll up through the spine rather than flinging your neck.",
      "Control the descent back to the floor."
    ],
    "common_faults": [
      {
        "fault": "Using excessive momentum or yanking the neck forward.",
        "correction": "Initiate the movement by contracting the abdominals and curling the ribcage toward the pelvis."
      },
      {
        "fault": "Crashing down onto the lower back during the eccentric phase.",
        "correction": "Resist gravity and unroll your spine vertebrae-by-vertebra back onto the floor."
      }
    ],
    "safety": {
      "precautions": [
        "Avoid this exercise if you have acute lower back pain exacerbated by combined spinal flexion and rotation."
      ],
      "spotter": "not-needed"
    }
  },
  "measurement": {
    "load": {
      "kind": "bodyweight"
    },
    "profiles": [
      {
        "required": [
          "reps"
        ],
        "optional": [
          "rpe"
        ]
      }
    ],
    "records": {},
    "reps_counted": "total"
  },
  "name": "Sprinter Sit-Up",
  "previous_ids": [
    "oec:splinter-sit-ups"
  ],
  "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: Splinter Sit-ups",
        "url": "https://wger.de/en/exercise/607/view-base",
        "license": "CC-BY-SA-3.0",
        "author": "djblitzd"
      }
    ]
  },
  "relations": [
    {
      "type": "variation-of",
      "target": "oec:sit-up"
    },
    {
      "type": "progression-of",
      "target": "oec:sit-up"
    },
    {
      "type": "progression-of",
      "target": "oec:bicycle-crunch"
    },
    {
      "type": "substitute-for",
      "target": "oec:twisting-sit-up"
    },
    {
      "type": "substitute-for",
      "target": "oec:bicycle-crunch"
    }
  ],
  "setup": {
    "position": "supine"
  },
  "status": "active",
  "summary": "A dynamic bodyweight core exercise that combines a full sit-up with a running stride motion to target the abdominals, obliques, and hip flexors."
}