Tons of threads on here that tend to be critical of intense training in younger kids. I think I agree with them in part because running is a sport that is more fun when you're continually progressing.
My question is - what do people suggest as the best training progression for young kids? I have 6th grade twins (boy and girl). My daughter especially loves her team and loves to run. She would train 7 days a week if we let her. At the moment I limit her to 4 days per week and max 18 miles (typically ~15). She runs workouts twice a week (intervals, tempo, fartlek) and two easy days with a long run of 5-6 miles. She's doing well and ran 5:38 for a 1600 a few weeks ago. Am I being too strict? What is a reasonable amount for an eighth grader, ninth grader etc. I think she can be good but I want her to keep enjoying the sport and I think a big part of that is leaving room to progress.