Body battery accuracy increased with chest strap?

As far as I understand the Body Battery isn't measured/calculated during activity, instead it is estimated using the activity intensity. In theory a chest strap should affect the estimation since the HR readings are used to get the intensity of the activity.

The picture below shows body battery including stress measurement for a whole day and during the two activities there is no measurement of stress:

Thanks Tobias,

I have found this in the manual on the body battery but no reference to a chest strap:

Tips for Improved Body Battery Data

• Your Body Battery level updates when you sync your device with your Garmin Connect account.

• For more accurate results, wear the device while sleeping.

• Rest and good sleep charge your Body Battery.

• Strenuous activity, high stress, and poor sleep can cause your Body Battery to drain.

• Food intake, as well as stimulants like caffeine, has no impact on your Body Battery.

Although the below snippet taken from the User Manual suggests the strap is used for body battery calculations it does not answer my question on if the accuracy of body battery will be improved if wearing a chest strap during an activity.

@HermanB 

@Garmin-Blake

The accuracy of a chest strap is with no doubt better than optical sensor. I've never checked for how long my chest strap stays connected after I stop and save an activity but regardless Body Battery is something that requires 24h monitoring and I would never wear a chest strap 24/7 :-)