Apple Fitness: 10km and 5km personal best incorrect

A couple of years ago I added a running workout to see if it would fill my rings and I was an impossibly fast time.

I’ve deleted the workout recently but the personal best badges remain these unobtainable times.

It’s very annoying because I’ve only just started running and I’m looking forward to improving my stats and gaining badges.

I thank you for any help resetting or restarting my 5km/10km personal best awards.