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# HKLiveWorkoutZoneUpdate

A structure that contains information about zone transitions during a live workout session.

```
class HKLiveWorkoutZoneUpdate
```

## Overview

This structure provides details about zone changes as they occur during a workout. The system sends updates to the [`HKLiveWorkoutBuilderDelegate`](/documentation/HealthKit/HKLiveWorkoutBuilderDelegate) when the person moves between zones.

## Topics

### Accessing update information

[`var lastSampleProcessedDate: Date?`](/documentation/HealthKit/HKLiveWorkoutZoneUpdate/lastSampleProcessedDate)

The timestamp of the most recent processed sample at the time of the update.

### Accessing zone data

[`var currentZoneDuration: HKWorkoutZoneDuration?`](/documentation/HealthKit/HKLiveWorkoutZoneUpdate/currentZoneDuration)

A property that contains the zone duration just entered.

[`var previousZoneDuration: HKWorkoutZoneDuration?`](/documentation/HealthKit/HKLiveWorkoutZoneUpdate/previousZoneDuration)

A property that contains the zone duration that just completed.

[`var zoneGroup: HKWorkoutZoneGroup?`](/documentation/HealthKit/HKLiveWorkoutZoneUpdate/zoneGroup)

The zone group that contains the current duration data.

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Sendable`](/documentation/Swift/Sendable)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

[`CVarArg`](/documentation/Swift/CVarArg)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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