In which way does the Heart Rate combine its reports with the Sports mode activity?

When you start a Sports activity with your device, you will have your Hear Rate visible on the Watch screen during the exercise.

When the activity is completed and the data uploaded into the App, you will be able to check the Heart Rate report during the exercise at the bottom of you your Heart Rate page.

There, you will have the duration and type of activity and the Heart Rate correspondence.

Taking note of your heart rate during your physical activities can help you monitor the intensity of your exercise.

In which way does physical activity affect the Heart Rate?