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# HKLiveWorkoutBuilder

A builder object that constructs a workout incrementally based on live data from an active workout session.

```
class HKLiveWorkoutBuilder
```

## Overview

Use a live workout builder to create an [`HKWorkout`](/documentation/HealthKit/HKWorkout) sample during an active [`HKWorkoutSession`](/documentation/HealthKit/HKWorkoutSession). For complete instructions on running workout sessions on Apple Watch, see <doc://com.apple.healthkit/documentation/HealthKit/running-workout-sessions>.

## Topics

### Configuring a live workout builder

[`dataSource`](/documentation/HealthKit/HKLiveWorkoutBuilder/dataSource)

A data source that provides live data from a workout session automatically.

[`workoutSession`](/documentation/HealthKit/HKLiveWorkoutBuilder/workoutSession)

The workout session created by the data source and associated with this builder.

[`delegate`](/documentation/HealthKit/HKLiveWorkoutBuilder/delegate)

The live builder’s delegate.

### Monitoring and controlling the workout

[`currentWorkoutActivity`](/documentation/HealthKit/HKLiveWorkoutBuilder/currentWorkoutActivity)

The current workout activity.

[`shouldCollectWorkoutEvents`](/documentation/HealthKit/HKLiveWorkoutBuilder/shouldCollectWorkoutEvents)

A Boolean value that determines whether the workout builder automatically adds events generated by the workout session.

### Accessing data

[`elapsedTime`](/documentation/HealthKit/HKLiveWorkoutBuilder/elapsedTime)

The elapsed time for the workout based on the builder’s current contents, including pauses.

### Receiving zone updates

[`HKLiveWorkoutZoneUpdate`](/documentation/HealthKit/HKLiveWorkoutZoneUpdate)

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


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