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# HKWorkoutZoneDuration

A structure that represents the time spent in a specific zone during a workout or activity.

```
struct HKWorkoutZoneDuration
```

## Overview

This structure pairs a zone with the duration of time the person spent in that zone. The system calculates durations based on quantity samples collected during the workout.

## Topics

### Accessing duration properties

[`let zone: HKWorkoutZone`](/documentation/HealthKit/HKWorkoutZoneDuration/zone)

A property that identifies the workout zone.

[`let duration: TimeInterval`](/documentation/HealthKit/HKWorkoutZoneDuration/duration)

A property that specifies the time spent in this zone, measured in seconds.

## Relationships

### Conforms To

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

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

---

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