Global Variable

HKQuantityTypeIdentifierRestingHeartRate

A quantity sample type that measures the user’s resting heart rate.

Declaration

const HKQuantityTypeIdentifier HKQuantityTypeIdentifierRestingHeartRate;

Discussion

These samples use count/time units (described in HKUnit) and measure discrete values (described in HKStatisticsQuery).

Resting heart rate is commonly correlated with overall cardiovascular health. It is an estimation of the user’s lowest heart rate during periods of rest, and is intended to be used as a medically relevant metric. A resting heart rate sample is different than a sedentary heart rate sample (that is, a sample using the HKQuantityTypeIdentifierHeartRate identifier with a HKHeartRateMotionContextSedentary motion context). For example, if the user finishes a high-intensity workout, and then sits down to rest, the next heart rate sample may be marked as a sedentary sample, but it is still much higher than the user’s actual resting heart rate. To produce more accurate results, the system estimates the resting heart rate by analyzing sedentary heart rate samples throughout the day.

Because the resting heart rate estimates become more accurate as the day progresses, the system may delete earlier samples and replace them with better estimates. Apple Watch replaces only the samples written by the watch for the current or previous day.

See Also

Vital Signs

HKQuantityTypeIdentifierHeartRate

A quantity sample type that measures the user’s heart rate.

HKCategoryTypeIdentifierLowHeartRateEvent

A category sample type for low heart rate events.

HKCategoryTypeIdentifierHighHeartRateEvent

A category sample type for high heart rate events.

HKCategoryTypeIdentifierIrregularHeartRhythmEvent

A category sample type for irregular heart rhythm events.

HKQuantityTypeIdentifierHeartRateVariabilitySDNN

A quantity sample type that measures the standard deviation of heartbeat intervals.

HKQuantityTypeIdentifierWalkingHeartRateAverage

A quantity sample type that measures the user’s heart rate while walking.

HKDataTypeIdentifierHeartbeatSeries

A series sample containing heartbeat data.

Beta
HKQuantityTypeIdentifierOxygenSaturation

A quantity sample type that measures the user’s oxygen saturation.

HKQuantityTypeIdentifierBodyTemperature

A quantity sample type that measures the user’s body temperature.

HKCorrelationTypeIdentifierBloodPressure

Blood pressure correlation types combine a systolic sample and a diastolic sample into a single blood pressure reading.

HKQuantityTypeIdentifierBloodPressureSystolic

A quantity sample type that measures the user’s systolic blood pressure.

HKQuantityTypeIdentifierBloodPressureDiastolic

A quantity sample type that measures the user’s diastolic blood pressure.

HKQuantityTypeIdentifierRespiratoryRate

A quantity sample type that measures the user’s respiratory rate.

HKQuantityTypeIdentifierVO2Max

A quantity sample that measures the maximal oxygen consumption during incremental exercise.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

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