Congrats on the personal best. I had one tonight as well. 10km in 59 min 30 seconds. I have been working on this one for a while. Glad I was running in the dark because I totally did a happy dance when I hit 10 km under an hour. Couldn't finish the last 300 metres because I was laughing. I have no problems with longer distances just getting my speed up. My thighs are still really thick and I think thats the main problem.