Is this a cross country or track term? What's it mean?

So my boyfriend is on the track and cross country team at our school, and he obviously runs a lot. I was texting him today and he sent me this message "‎11:05 in the 2 mile today! PR'd by half a minute! :)" What does PR'd mean? Haha. I didn't want to dampen the mood by asking him that, so I didn't. But I am curious as to what the means. Any thoughts?