sub 4 for super elites on a banister like program
figuring out a schedule for the aerobic component call it 3 miles a day with 10 minutes slow exercise bike warmup. or breath work.
=========================
4 x 800 m uphill hard walk down full recovery and 1 1/2 mile steady
3 miles cross country
200 x 6 fast full recovery 300 x 4 moderate fast full recovery
4 miles cross country
20 x 150m strides fast and easy full recovery plus 1 1/2 mile steady
off
4 miles cross country
the aerobic runs are not super duper hard but surely stressing the system, to adapt upward, the last mile might be threshold or so.
something like that.
formerly really fit guys that are coming off a lay off, this kind of schedule will renew the juice. mentally they are equipped to attack this with quality.