Most guys my age trying to get in shape for a mile fit into one of two categories.
1) 400/800m specialists moving up in distance. Their plan is simple: lower 400m time as much as possible and practice running mile pace for longer and longer, ideally hitting 1200m at pace in training once before racing. Then do a bunch of track races, waiting for conditions to be right for an attempt at a record.
2) 5K road specialists who do a few mile races each year. They have their previous times to use as a guide and either do no specific training or 2-3 specific workouts as a test that they use each year. 10x400m at mile pace is standard.
There's not much for: guy who trained to run a trail 100 mile last year, spent the winter rehabbing injuries, threw out his back, got the flu, has no access to an actual track and has maybe 12 weeks to train before the only local races - and it's still snowing.
I'm planning on using two killer workouts. The idea is to maximize oxygen uptake, increase the pace run at maximal uptake, increase time that can be run at that pace until lactic acid build-up, increase time that can be run while building up lactic acid and increasing the speed run while in anaerobic lactic phase - in that order. This will be done with two alternate weekly killer workouts.
M 6 miles
T 8, last 3 faster (ideally 15K/10 mile pace)
Sa 6 miles INTERVALS
Interval workout 1: 1200m @ 5k, 600m easy, 1200@5k, 600, 1200@5K, 600, 1200@5K, 400 all-out, 1000 easy, 400 all-out.
Alternate workout 2: 600m @ 3K, 200easy, 600@3K, 200, 600@3K, 200, 600@3k, 200, 600@3k, 1000 time-trial (aiming for mile pace)
These are versions of a workout known as "lactate stackers." The standard way these are done is to run 400-1200m as hard as possible, then, without recovery, run another 400-800m as fast as possible (necessarily slower than the first part). My workouts are at the bottom and top ends of MVO2 speeds, done essentially to exhaustion, then followed by hard runs when already tired. The first one has a second hard 400m after a recovery to show that even when exhausted, there's "still something left in the tank."
These are maniacally tough workouts. We'll see how they go. It looks like I'll have to shovel off a cinder track this Saturday to find out...