If you run with iSmoothRun and Stryd, there are various ways to get power data into PowerCenter.
1. You can export the data from iSmoothRun from with the app. You can email yourself the .TCX file of your activity. That file can be imported into PowerCenter under http://stryd.com/powercenter/settings (scroll to the bottom).
2. You can link iSmoothRun to Garmin Connect from within the iSmoothRun app (under settings, go to social & export). Then, link PowerCenter to Garmin Connect. This way, your iSmoothRun data will flow automatically into PowerCenter.
3. Import your data directly from Stryd with the Stryd app on your phone.
Note that the recording interval in iSmoothRun may not be each second. If the recording interval is not second by second, PowerCenter will show a jagged pace and power profile. This is a limitation of iSmoothRun.
If you need additional assistance, contact firstname.lastname@example.org