Just to throw in my two cents...keep your running distance variable. Same thing goes for the shoes you wear, surfaces you run on, and workouts you do. Homogeneity leads to overuse injuries, stagnation, and/or burnout.
Rotate.
That said, you can still run the same distance every day without running the same distance every run. Doubles are key. Here is a sample:
Sunday: 5 miles easy
Monday: 16 miles total, with 8 miles of tempo and 8x100m strides
Tuesday: AM - 9 miles, PM - 5 miles (14 total)
Wednesday: AM - 10 miles, PM - 5 miles (15 total)
Thursday: 16 miles total, with 2 miles of tempo, 8x1000m intervals, and 6x200m hill charges
Friday: AM - 8 miles, PM - 6 miles (14 total)
Saturday: 20 miles easy, with 8x100m strides. Done on dirt road or trail.
Good reference article:
http://therunzone.com/trom.htmlSteve, in essence what your coach is saying is
be consistent. Don't miss days, and don't vary your mileage all over the board. Don't do any runs shorter than 5 miles, nor any runs longer than 10 miles. But running exactly 6 miles each run can lead to the things I mentioned above.
I would suggest doubles to you, if you coach is okay with it. You obviously have a lot of free time during your days, which you could use to train more. If you average something like 12 miles/day in doubles, you will become tremendously fit for 5K XC without putting too much strain on your body.