通过HRV跟踪节拍击败心率苹果手表

Question

我正在研究如何获得单独心跳间隔的逐搏间隔。

我戴着Apple Watch，目前我可以出口

<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>

然而，当我得到heartRateVariabilitySDNN的样本时，我只得到了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)
        }
    }

这就是它输出的全部内容：

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)])

基本上是2个值：92.7ms和92.3ms。这些是Watch上“呼吸”应用期间2次训练的平均值。

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

编辑：似乎有一些有趣的事情，输出值看起来非常像XML中的Record类型的print语句。

Answer 1

在向Apple提交技术支持事件（TSI）之后，他们表示目前无法做到这一点。

感谢您与Apple开发人员技术支持（DTS）联系。我们的工程师已经审核了您的请求，并得出结论，鉴于当前出货的系统配置，没有支持的方法来实现所需的功能。

如果您希望Apple将来考虑添加对此类功能的支持，请通过https://developer.apple.com/bug-reporting/上的Bug Reporter工具提交增强请求。

如果您想看到此功能，请提交错误报告！

Answer 2

如果你想获得瞬时心率，你的应用应该开始HKWorkoutSession。

    self.workoutSession = HKWorkoutSession(activityType: .Running, locationType: .Indoor)
    self.workoutSession!.delegate = self;

    self.healthStore.startWorkoutSession(self.workoutSession!)

Then, you can start a streaming query from HKHealthKit to give you updates as HealthKit receives them:

    let distanceType = HKObjectType.quantityTypeForIdentifier(HKQuantityTypeIdentifierDistanceWalkingRunning)
    let predicate = HKQuery.predicateForSamplesWithStartDate(workoutStartDate, endDate: nil, options: .None)
    let distanceQuery = HKAnchoredObjectQuery(type: distanceType!, predicate: predicate, anchor: 0, limit: 0) { (query, samples, deletedObjects, anchor, error) -> Void in
        // Handle when the query first returns results
        // TODO: do whatever you want with samples (note you are not on the main thread)
    }
    distanceQuery.updateHandler = { (query, samples, deletedObjects, anchor, error) -> Void in
        // Handle update notifications after the query has initially run
    }

    self.healthStore.executeQuery(distanceQuery)