Mapping — Strong

Source: Strong app CSV export (one row per set; , or ; delimited). Pillar: B (strength). Mapper: mapStrong — mapStrong(csv) → { records, warnings }, one Session per workout.

Structural correspondence

Strong CSV	OpenBody
a workout (rows sharing Date + Workout Name)	Session (disciplines: ["strength"], name ← Workout Name, clientRecordId ← the natural key)
consecutive rows for one Exercise Name	Exercise (exerciseRef: canonical registry id where the crosswalk resolves the name, plus the lossless opaque original)
one set row	WorkUnit (scoring from Reps/Distance/Seconds)
Weight	performance.load (unit: "kg", basis: "marked_weight")
Reps / Distance / Seconds	performance.reps / .distance (m) / .time (s)
Notes	WorkUnit.notes
Workout No	Session.extension["io.strong.export"].workoutNo

Input (two exercises, one of them a plank)

Date,Workout Name,Duration,Exercise Name,Set Order,Weight,Reps,Distance,Seconds,Notes,Workout No
2025-12-20 18:00:00,Push Day,3600,Bench Press (Barbell),1,80,5,0,0,,1
2025-12-20 18:00:00,Push Day,3600,Plank,1,0,0,0,60,core hold,1

Output (OpenBody wire record)

{
  "id": "strong-w-87ab88ae",
  "recordType": "Session",
  "subject": "subj-001",
  "clientRecordId": "2025-12-20 18:00:00|Push Day",
  "disciplines": ["strength"],
  "startTime": "2025-12-20T18:00:00Z",
  "endTime": "2025-12-20T19:00:00Z",
  "name": "Push Day",
  "extension": { "io.strong.export": { "workoutNo": "1" } },
  "exercises": [
    {
      "id": "strong-w-87ab88ae-ex0",
      "recordType": "Exercise",
      "exerciseRef": { "id": "bench-press.barbell.flat", "opaque": "Bench Press (Barbell)" },
      "workUnits": [
        {
          "id": "strong-w-87ab88ae-ex0-set0",
          "recordType": "WorkUnit",
          "scoring": "reps",
          "performance": { "reps": 5, "load": { "value": 80, "unit": "kg", "basis": "marked_weight" } }
        }
      ]
    },
    {
      "id": "strong-w-87ab88ae-ex1",
      "recordType": "Exercise",
      "exerciseRef": { "id": "plank", "opaque": "Plank" },
      "workUnits": [
        {
          "id": "strong-w-87ab88ae-ex1-set0",
          "recordType": "WorkUnit",
          "scoring": "time",
          "performance": { "time": 60 },
          "notes": "core hold"
        }
      ]
    }
  ]
}

Notes

• Stable ids. The export has no workout id of its own, so the natural key (Date|Workout Name) becomes clientRecordId (§7.1) and a content hash of it the record id — positional numbering would renumber everything when one more workout is exported, defeating dedup.
• Duration (seconds) sets endTime = startTime + Duration.
• Timestamps. Strong’s Date is wall-clock with no offset; the mapper stamps it with the optional utcOffset option (default "Z"), never the machine’s local timezone — the same bytes map to the same records everywhere.
• App-specific residue (Workout No) has no canonical home, so it goes to a namespaced extension (io.strong.export) rather than being dropped — the canonical-plus-residue principle (§10.1).
• Mixed scoring per exercise works: a Plank row (Seconds: 60) becomes a time-scored WorkUnit; a distance row becomes distance-scored.
• Exercise identity resolves to canonical registry ids where the crosswalk covers the name (both names above resolve), keeping the opaque original alongside — like Hevy.
• The mirror direction exists too: mapOpenBodyToStrong writes this same CSV shape back out.