{
  "data": {
    "metrics": [
      { "name": "heart_rate", "units": "count/min",
        "data": [ { "date": "2026-10-04 08:00:00 +0100", "qty": 71.5, "Min": 62, "Max": 88, "Avg": 71.5 },
                  { "date": "2026-10-04 09:00:00 +0100", "qty": 76.2, "Min": 64, "Max": 104, "Avg": 76.2 } ] }
    ]
  }
}