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# workoutBuilder(_:didBegin:)

Tells the delegate that a new workout activity has started.

```
optional func workoutBuilder(_ workoutBuilder: HKLiveWorkoutBuilder, didBegin workoutActivity: HKWorkoutActivity)
```

## Parameters

`workoutBuilder`

The workout builder that received the new activity.

`workoutActivity`

A new workout activity, currently in progress.

---

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