---
title: lowHeartRateEvent
framework: healthkit
role: symbol
role_heading: Type Property
path: healthkit/hkcategorytypeidentifier/lowheartrateevent
---

# lowHeartRateEvent

A category sample type for low heart rate events.

## Declaration

```swift
static let lowHeartRateEvent: HKCategoryTypeIdentifier
```

## Discussion

Discussion The system creates lowHeartRateEvent samples whenever Apple Watch produces a low heart rate notification. For more information, see Heart rate notifications on your Apple Watch. The low heart rate samples are read-only. You can request permission to read the samples using this identifier, but you can’t request authorization to share them. This means you can’t save new low heart rate events to the HealthKit store. To add test data in iOS Simulator, open the Health app and select Browse > Heart > Low Heart Rate Notifications > Add Data. These samples have a value of HKCategoryValue.notApplicable and include HKMetadataKeyHeartRateEventThreshold metadata.

## Topics

### Metadata Keys

- [HKMetadataKeyHeartRateEventThreshold](healthkit/hkmetadatakeyheartrateeventthreshold.md)

## See Also

### Vital signs

- [heartRate](healthkit/hkquantitytypeidentifier/heartrate.md)
- [highHeartRateEvent](healthkit/hkcategorytypeidentifier/highheartrateevent.md)
- [irregularHeartRhythmEvent](healthkit/hkcategorytypeidentifier/irregularheartrhythmevent.md)
- [restingHeartRate](healthkit/hkquantitytypeidentifier/restingheartrate.md)
- [heartRateVariabilitySDNN](healthkit/hkquantitytypeidentifier/heartratevariabilitysdnn.md)
- [heartRateRecoveryOneMinute](healthkit/hkquantitytypeidentifier/heartraterecoveryoneminute.md)
- [atrialFibrillationBurden](healthkit/hkquantitytypeidentifier/atrialfibrillationburden.md)
- [walkingHeartRateAverage](healthkit/hkquantitytypeidentifier/walkingheartrateaverage.md)
- [HKDataTypeIdentifierHeartbeatSeries](healthkit/hkdatatypeidentifierheartbeatseries.md)
- [HKElectrocardiogramType](healthkit/hkelectrocardiogramtype.md)
- [oxygenSaturation](healthkit/hkquantitytypeidentifier/oxygensaturation.md)
- [bodyTemperature](healthkit/hkquantitytypeidentifier/bodytemperature.md)
- [bloodPressure](healthkit/hkcorrelationtypeidentifier/bloodpressure.md)
- [bloodPressureSystolic](healthkit/hkquantitytypeidentifier/bloodpressuresystolic.md)
- [bloodPressureDiastolic](healthkit/hkquantitytypeidentifier/bloodpressurediastolic.md)