ios - 通过 HRV 跟踪节拍以节拍心率 Apple Watch

Question

我正在研究获取单独心跳间隔的逐次心跳间隔的方法。

我戴着 Apple Watch，目前可以导出

<Record type=“HKQuantityTypeIdentifierHeartRateVariabilitySDNN” sourceName=“Apple Watch” sourceVersion=“4.0” device=“&lt;&lt;HKDevice: 0x1c489da10&gt;, name:Apple Watch, manufacturer:Apple, model:Watch, hardware:Watch3,4, software:4.0&gt;” unit=“ms” creationDate=“2017-10-31 13:41:54 +0000" startDate=“2017-10-31 13:40:43 +0000” endDate=“2017-10-31 13:41:54 +0000" value=“92.7156”>
  <HeartRateVariabilityMetadataList>
   <InstantaneousBeatsPerMinute bpm=“69" time=“13:40:45.22”/>
   <InstantaneousBeatsPerMinute bpm=“74" time=“13:40:46.02”/>
   <InstantaneousBeatsPerMinute bpm=“71" time=“13:40:46.87”/>
   <InstantaneousBeatsPerMinute bpm=“64" time=“13:40:47.81”/>
   <InstantaneousBeatsPerMinute bpm=“54" time=“13:40:48.92”/>
   <InstantaneousBeatsPerMinute bpm=“57" time=“13:40:49.97”/>
   <InstantaneousBeatsPerMinute bpm=“65" time=“13:40:50.90”/>
   <InstantaneousBeatsPerMinute bpm=“63" time=“13:40:51.86”/>
   <InstantaneousBeatsPerMinute bpm=“60" time=“13:40:52.86”/>
   <InstantaneousBeatsPerMinute bpm=“57" time=“13:40:53.92”/>
   <InstantaneousBeatsPerMinute bpm=“57" time=“13:40:54.98”/>
   <InstantaneousBeatsPerMinute bpm=“61" time=“13:40:55.97”/>
   <InstantaneousBeatsPerMinute bpm=“70" time=“13:40:56.83”/>
   <InstantaneousBeatsPerMinute bpm=“72" time=“13:40:57.66”/>
   <InstantaneousBeatsPerMinute bpm=“69" time=“13:40:58.54”/>
   <InstantaneousBeatsPerMinute bpm=“58" time=“13:40:59.58”/>
   <InstantaneousBeatsPerMinute bpm=“58" time=“13:41:02.75”/>
   <InstantaneousBeatsPerMinute bpm=“63" time=“13:41:03.70”/>
   <InstantaneousBeatsPerMinute bpm=“70" time=“13:41:04.56”/>
   <InstantaneousBeatsPerMinute bpm=“70" time=“13:41:05.41”/>
   <InstantaneousBeatsPerMinute bpm=“69" time=“13:41:13.15”/>
   <InstantaneousBeatsPerMinute bpm=“71" time=“13:41:13.99”/>
   <InstantaneousBeatsPerMinute bpm=“63" time=“13:41:21.11”/>
   <InstantaneousBeatsPerMinute bpm=“69" time=“13:41:21.98”/>
   <InstantaneousBeatsPerMinute bpm=“73" time=“13:41:22.79”/>
   <InstantaneousBeatsPerMinute bpm=“65" time=“13:41:35.27”/>
   <InstantaneousBeatsPerMinute bpm=“67" time=“13:41:36.17”/>
   <InstantaneousBeatsPerMinute bpm=“71" time=“13:41:37.01”/>
   <InstantaneousBeatsPerMinute bpm=“77" time=“13:41:37.79”/>
   <InstantaneousBeatsPerMinute bpm=“79" time=“13:41:38.55”/>
  </HeartRateVariabilityMetadataList>
 </Record>

但是，当我获取 heartRateVariabilitySDNN 的样本时，我只返回 2 个值。

这是我用来获取样本的代码

  let healthStore = HKHealthStore()

    var typeHeart = HKQuantityType.quantityType(forIdentifier: .heartRateVariabilitySDNN)
    var startDate = Date() - 7 * 24 * 60 * 60 // start date is a week
    var predicate: NSPredicate? = HKQuery.predicateForSamples(withStart: startDate, end: Date(), options: HKQueryOptions.strictEndDate)

    let sampleType = HKSampleType.quantityType(forIdentifier: HKQuantityTypeIdentifier.heartRateVariabilitySDNN)

    let sortDescriptor = NSSortDescriptor(key:HKSampleSortIdentifierStartDate, ascending: false)

    let sampleQuery = HKSampleQuery(sampleType: sampleType!, predicate: predicate, limit: 30, sortDescriptors: [sortDescriptor])
    { (sampleQuery, results, error ) -> Void in
        if(error == nil) {
            print(results)
        }
    }

这是它输出的所有内容:

Optional([92.3536 ms D7627860-F87C-4316-9943-522BC1D6734B "Apple Watch" (4.0), "Watch3,4" (4.0)"Apple Watch"  (2017-10-31 13:48:19 +0000 - 2017-10-31 13:53:30 +0000), 92.7156 ms EB0DBCB1-164A-4D50-9103-270F3F9FBCD1 "Apple Watch" (4.0), "Watch3,4" (4.0)"Apple Watch"  (2017-10-31 13:40:43 +0000 - 2017-10-31 13:41:54 +0000)])

这基本上是 2 个值:92.7 毫秒和 92.3 毫秒。这些是 watch 上“呼吸”应用期间 2 次锻炼的平均值。

有谁知道如何获取InstantaneousBeatsPerMinute 和/或 HRV 元数据？

编辑:似乎发生了一些有趣的事情，输出值看起来非常像 XML 中 Record 类型的打印语句。

Answer 1

在就此向 Apple 提交技术支持事件 (TSI) 后，他们表示目前无法执行此操作。

Thank you for contacting Apple Developer Technical Support (DTS). Our engineers have reviewed your request and have concluded that there is no supported way to achieve the desired functionality given the currently shipping system configurations.

If you would like for Apple to consider adding support for such features in the future, please submit an enhancement request via the Bug Reporter tool at https://developer.apple.com/bug-reporting/.

如果您想看到此功能，请提交错误报告!