Last year in high school I ran 1:55 and 4:14mile with running around 6:40pace on my runs. However this year I struggled in cross country after my coach told me 6:40s is way to slow. I bumped up to 6:15-6:20s but my racing went down hill. My goal this year is to run under 4min for the mile. What type of pace should by distance runs be at while keeping my workouts good quality? Suggestions on workouts? What type of things should I focus on to improve that my coach may not have thought of?