From my experience I ran park run and on the 3 or 2 loop I kept on saying to myself RUNNERS NEVER QUIT over and over again. But the one reason I did it was so I could prove myself to my friends and family and I did finish.But if your not used to it you may want to train before you do a 5k run. I had massive pain in my legs and could not walk properly. But if you do a 5k run you might want to run with someone like I ran with my Daddy and my dog Max. And because I am only 9 I do not really run that much because of school. But for adults you have more time then children so you can mark when to train on school days. Just in case you want to go Park Run is mostly on Saturday.But you must remember RUNNERS NEVER QUIT!!