I did a speed workout last night. It consisted of a 1 mile warm up, 12 x 400m, and a 1 mile cool down. My 620 froze after the 2nd or 3rd repeat and I had to do a reset. The activity was still there when it restarted so I was able to pick up where I left off. Things did get a little wonky and I ended up doing an extra repeat somehow. I either lost count when the Garmin froze or something similar. Anyway, after I was done I got an alert that I had 3 new records, 1mi, 5k, & 10k. It's saying I have a new 1mi record of 0:31, a new 5k of 19:08, and a new 10k of 46:51. I'm not sure where it's coming up with those because I definitely didn't do any of those distances in any of those times. Below is a link to the workout, I would really appreciate it if someone could help shed some light on how it's calculating those times and distances.
http://connect.garmin.com/activity/494500912