I graduated from C25k about 9 weeks ago and went up from 3 X 30 mins, to adding in a 5k, then 3 X 5k. I still found that distance a slog and challenging every time. A couple of weeks ago early in the morning, I felt really good as if I could keep going, so just ran on to 5.5k which surprised me. Last week, same happened and ran on to 6k and now as my legs are going well and recovery is great, going to try 6k X 3 and settle at that for a month. One minute, a distance seems horrible and then for no real reason, feels easier! Cannot believe I can run 6k, took me by surprise - need to find bigger places to run now!!