{
  "schema_version": "1.0",
  "plan": {
    "id": "couch-to-5k-base",
    "name": "Couch to 5K Base",
    "author": "Universal Fit",
    "description": "A gentle run-walk progression for building consistent aerobic work without needing GPS inside the plan file.",
    "goal": "endurance",
    "level": "beginner",
    "duration_weeks": 4,
    "days_per_week": 3,
    "tags": ["running", "cardio", "bodyweight"]
  },
  "settings": {
    "units": { "weight": "kg", "distance": "km" }
  },
  "weeks": [
    {
      "week": 1,
      "days": [
        {
          "day": 1,
          "name": "Run-Walk Intro",
          "estimated_minutes": 30,
          "blocks": [
            {
              "type": "main",
              "items": [
                {
                  "kind": "exercise",
                  "exercise_ref": "running",
                  "cardio": {
                    "structure": "intervals",
                    "modality": "running",
                    "warmup": { "duration_minutes": 5 },
                    "intervals": [{ "repeat": 8, "work": { "duration_minutes": 1 }, "rest": { "duration_seconds": 90, "type": "walk" } }],
                    "cooldown": { "duration_minutes": 5 }
                  }
                }
              ]
            }
          ]
        },
        { "day": 3, "name": "Easy Repeat", "estimated_minutes": 30, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "steady", "modality": "running", "target": { "duration_minutes": 25, "rpe_target": 4 } } }] }] },
        { "day": 5, "name": "Run-Walk Intro", "estimated_minutes": 30, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "intervals", "modality": "running", "warmup": { "duration_minutes": 5 }, "intervals": [{ "repeat": 8, "work": { "duration_minutes": 1 }, "rest": { "duration_seconds": 90, "type": "walk" } }], "cooldown": { "duration_minutes": 5 } } }] }] }
      ]
    },
    {
      "week": 2,
      "days": [
        { "day": 1, "name": "Longer Jog Blocks", "estimated_minutes": 32, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "intervals", "modality": "running", "warmup": { "duration_minutes": 5 }, "intervals": [{ "repeat": 6, "work": { "duration_minutes": 2 }, "rest": { "duration_seconds": 90, "type": "walk" } }], "cooldown": { "duration_minutes": 5 } } }] }] },
        { "day": 3, "name": "Easy Aerobic", "estimated_minutes": 30, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "steady", "modality": "running", "target": { "duration_minutes": 28, "rpe_target": 4 } } }] }] },
        { "day": 5, "name": "Longer Jog Blocks", "estimated_minutes": 32, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "intervals", "modality": "running", "warmup": { "duration_minutes": 5 }, "intervals": [{ "repeat": 6, "work": { "duration_minutes": 2 }, "rest": { "duration_seconds": 90, "type": "walk" } }], "cooldown": { "duration_minutes": 5 } } }] }] }
      ]
    },
    {
      "week": 3,
      "days": [
        { "day": 1, "name": "Three-Minute Repeats", "estimated_minutes": 35, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "intervals", "modality": "running", "warmup": { "duration_minutes": 5 }, "intervals": [{ "repeat": 5, "work": { "duration_minutes": 3 }, "rest": { "duration_seconds": 120, "type": "walk" } }], "cooldown": { "duration_minutes": 5 } } }] }] },
        { "day": 3, "name": "Easy Aerobic", "estimated_minutes": 32, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "steady", "modality": "running", "target": { "duration_minutes": 30, "rpe_target": 4 } } }] }] },
        { "day": 5, "name": "Three-Minute Repeats", "estimated_minutes": 35, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "intervals", "modality": "running", "warmup": { "duration_minutes": 5 }, "intervals": [{ "repeat": 5, "work": { "duration_minutes": 3 }, "rest": { "duration_seconds": 120, "type": "walk" } }], "cooldown": { "duration_minutes": 5 } } }] }] }
      ]
    },
    {
      "week": 4,
      "days": [
        { "day": 1, "name": "Continuous Easy Run", "estimated_minutes": 35, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "steady", "modality": "running", "target": { "duration_minutes": 30, "rpe_target": 5 } } }] }] },
        { "day": 3, "name": "Recovery Walk Jog", "estimated_minutes": 30, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "fartlek", "modality": "running", "target": { "duration_minutes": 28 }, "notes": "Alternate easy jogging and walking by feel." } }] }] },
        { "day": 5, "name": "5K Confidence Day", "estimated_minutes": 40, "blocks": [{ "type": "main", "items": [{ "kind": "exercise", "exercise_ref": "running", "cardio": { "structure": "steady", "modality": "running", "target": { "distance_km": 5, "rpe_target": 6 } } }] }] }
      ]
    }
  ]
}