Yeah, it depends on the type of runner you are. I was usually a 49 low 4x4 split runner and probably would have maxed out around 3:55 for 1500m (ran 4:00+ in my only attempt), but was able to run 1:49 a handful of times. All of which I was through the 600m in around 1:21.
I maxed out at 35mile weeks in the summer with about an 8 mile long run. Started doing longer interval and hill workouts (30-45sec effort on a steep hill) in the fall. You'll see tons of different advice on here. I didn't have exceptional speed or natural endurance. Didn't do many tempo runs… most everything was harder intervals on the track (or in the grass) 1000m and down (once fall started)
When trying to get into peak form would do a 500m 300m 200m at race pace. with plenty of rest in between. It was a lot of race pace stuff. Early in the spring it'd be 1k, and down ladders… later in the year would start at 600m for the longest rep.
As a pure 800m (as you say you are; as I think I was), you need to be able to get to 600m in at least 1:23 if you want to break 1:52, so the speed endurance stuff is key. You likely don't run the mileage to kick people down or really surge in the final 200m, so you really have to focus on the 3rd 200m. get to 600m and then hang on for dear life. That was my experience at least. First time I broke 1:50, I went out in 51.0 in 5th or 6th place… just hung on. When I'd hang back in races, I never had any significant juice. The best time to do work was early in the race.
Here are some sessions from 2 weeks out from conf. championships:
Monday: Workout:
500m (1:06), 4min jog recovery
2x200m (25.7, 26.0), 2min jog in between.
8min walk/jog rest
then (2x150m, 2x100m) = 90% effort
Wednesday workout:
(300, 200) x3. 2min between reps, 8min between sets.
41.1
26.0
41.2
26.1
40.5
26.5
The long rest was necessary to make sure you can do the intervals at a rate that your legs are going to feel during the race. The rest was active but certainly not 8min/mi pace or anything. It was a shuffle at best.
Anyways, best of luck.