So currently a sophomore in high school with pretty good freshmen times and mediocre sophomore times while training with the distance group. My last year's PR's in the 400m was 57 and 800m was 2:13 but this year I've only gotten 58 in a 4x400 relay and a 2:23 in an 800m open while training with the distance group. I was recently approached multiple times by the coach to possibly switch off from the distance group and instead switch to spiriting group to train for the 400/800m but I'm still pretty unsure of what to do. Like most high schools, the sprinters run short distances and longer break times between intervals while the distance runners do longer intervals, hills and long runs. I was wondering if in order to improve my times in the 800m and 400m the most, would it be more effective to continue running with the distance crew in the long runs and longer intervals, join the sprinters and work on my speed or rotate between the groups every other day.
Also asking if it would be better to play to my strengths and work on speed or work on improving my weakness which would be doing more longer runs independently.
PS: Last year in winter my PR's were 2:40 in the 800m (never ran the 400) and I improved by doing about 45 miles a week during the preseason for a month or so allowing me to eventually end up with a 2:13 and 57.