How do generate reports.

You must be referring to generating health reports from the Health app on your iPhone.

There is no direct way to generate a health report from the health app. As you already know, you can see trends and all data associated with it for a given category on your iPhone's screen. You can take screen shots of the data if you like.

You have a good recommendation and if you would like Apple to consider this feature then please leave feedback here ➔ Product Feedback - Apple

Axel F.