I'm not really a competitive runner... I just run for fitness (and mental health )... I've gradually worked up to 5.5 miles 4 or 5 days per week over 9 months or so. I run at a comfortable pace, which many of you might call jogging, although I'm always under a 10 minute mile. I STILL find that I'm very sore from running most of the week. Any idea when this might improve?