This 600m to 800m translation brings up a good issue, which is just about peaking, splits, and guts. While not all races go this way, I am firmly in the camp that you have to prepare yourself in the 800m for a slog it out, positive split, fight the lactic acid last 100m kind of race. Particularly as you get into better, more deep competitive races (even at HS state meets) you are going to have a race out of the lanes to get position for the first 200m which will dictate a large part of the race. In waterfall starts perhaps this is mitigated a bit since position is set after the first 50m or so. Even or negative split races are not rare, but the minority once you got to the college level. Something to address later. If I were to throw out a guess I am going to say that at the college level and beyond 80% of the races positive split, so for training we need to feature that style or you simply wont feel comfortable and be competitive. I understand that you can "run your own race" and hang back 5-8m off a hot pace for the first 600m, but you can rarely hang back 20m (about 2.5 seconds) until late in the race and work yourself around all 8 people and win. If you are a superior talent in HS running against mortals then fine, but you were going to win the race anyway.
How this relates to peaking is that I firmly believe that you have two broad categories of training reponses in your body and that as a coach or self-coached athlete...physiological and endocrine. Physiological changes include muscle adaptation, capillary development, vo2max improvement, red blood cell density....many books on the subject. This is brought about by creating a consistant environment of running stress to your body, thus the idea for even an 800m person to run mileage, and to work a great deal of the year on strength and multi-levels of trigger points (aerobic, LT, longer intervals,etc). The error most common this period of time I have seen is three-fold:
1. Introducing new stimulus too abruptly. You are not trying to "shock" the runners system, but incrementally stress it to adapt. Runners should not be changing phases in a week (ie coming back from running LSD all summer long to doing 3 interval sessions the first week of XC) but should ease into any new phase slowly with gradualism. Coaches should be controlling first week of practice anytime, since runners will go from running alone to running in groups which ups the pace everyday.
2. In the effort not to "shock" the system too rapidly, you cannot let any of the various energy systems completely atrophy during the year for an 800m runner. If you are going to need a CP system and anaerobic system to power you, you have to be doing a minimal amount of work at those levels to keep it active and build a mini "base" in those areas even during the base phase.
3. With regard to base-period "speed" work, as a coach and athlete you have to have the discipline to do this as less than goal pace. Mentally it is difficult as an athlete -- you simply dont want to be running 200s at a moderate pace. Monday after a distance run an elite athlete might run 6*200m in October in 36-34-32 to just start working this system, and by January that session is down to 30-28-26. By the time you get to the spring and you want to tune up the speed phase, running 26-24-22 is just a natural progression and promotes a feeling in the athlete of relaxed running at speed.
Peaking is controlled by stimulating the endocrine response, primarily for 800m in stimulating your body to produce more lactic acid buffers in the blood and to increase blood volume. Endocrine systems as we discussed are highly subject to habituation (ie they will start ignoring the training stimulation soon and the positive affects will receed). This is different in every athlete, but in my experience you can stretch out somewhere between a 3-6 week peak performance period. To get this final effect, you do need to "shock" the athlete's system somewhat, which is most often done with high-intensity, race like intervals that are very specific to the race and entirely anaerobic. 300m-600m intervals FASTER THAN race pace are important catalysts for this process, all within 2-4 weeks of the hoped for peak.
400-1500 Coach makes a good point--apples to apples you should be able to "race" a 600m faster than you time-trial a 600m in practice. I never raced a 600m but he is correct, I am certain that I would have run faster than anything i turned out in practice. But they wouldnt have been that far away from eachother. If I felt an athlete was capable of 1:50.0 in the 800m,I would want them to hit 1:20 in a 600m in practice, and not something slower. I want them to be fighting through the lactic acid of the last 200m and feel the burn of the acidosis. I want their legs tying up and the electrical nerve signals having a difficult time translating through the acidic environment and calcium spent muscle cells (remember that soreness has been found recently not to be lactic acid but leaked calcium in the muscles -- lactic acid is cleared out fairly quickly). Allow the athlete 8 minutes to recover all energy systems, then have to produce a high effort 400m (within 2 seconds of all out). finish with a few 200s focusing on pure turnover to make certain youve exhausting both the power-off muscle systems in the legs but also the carriage (bringing your legs through).
One way to make certain the athlete is doing this is to tell them to run near full effort the first 400m of the 600m. You purposely want them to go out too fast in this session. Not only are you certain to shock the anaerobic system, but also mentally you are callousing the runner to the pain of that last 200m and giving them confidence. A session or a few sessions like this are important, but only in that zone timed nearest to competition.
Let's face it, while talent and preparation have everything to do with putting you in position and having the potential to lift the last 100-150m, it takes some grit and determination to ignore the body telling you to slow down. We have all seen runners that just dont have it, or where it is not there some days. I dont know if you can teach this, but you can definately test it before race day. To fully prepare the athlete, they need to feel that sensation before race day since it is human to fear less then devil you know than the devil you dont know.
apologies for long rant...its cold here in Seattle with no football on.