Yes, you can export all of your data from the Health app by clicking on your profile image in the upper right corner and scrolling all the way down to “Export All Health Data.” There are also a few third-party apps, such as Health Auto Export - JSON+CSV that give you a bit more control over the export format and allow you to select the data you want to export. I’ve used the app referenced above when I performed a detailed comparison of my heart rate data captured by WHOOP, Apple Watch and a third-party chest strap.