@My 2 Cents,
Thanks for the detailed reply, I appreciate. And like I said, no rush for the marathon, around age 24-25 would probably be a good time. I like 5k races a lot, and would like to develop some before moving up, because like you said, you need speed for a good marathon(which is likely why marathoners are faster now than before because they move up sooner while they have more speed).
My HS training was inconsistent and all over the place. (long post coming):
Freshmen year I started running in xc and probably did 4-6 miles a day 5 days a week until end of the season(20:26 5k) when I started running on weekends, then I got into the rhythm of running year round. Did about 35-40 mpw rest of freshmen year. 45 mpw most of sophomore year where I lowered my 5k to 1744. But I was mad cuz I got beat by a freshmen so I overtrained that winter and spring. Then summer and fall following that I tried taking my easy days ridiculously easy (9-10 pace) instead of my regular 750-800 pace at the time(because I read Kenyans took easy days easy) and got really out of shape. Then after junior xc I took advice of a 909 2 miler friend and followed a very well structured long base phase he set up for me that started nearly from scratch. The easy start helped me shake off the mental/physical burnout I had dating back to winter of sophomore year. I had a less than stellar track season, but I was finally getting back to my sophomore year shape coming very close to my track prs(ran 449 15, 223 8, 1026 3k that season).
Then in the summer I followed my friend's training advice again but built up faster this time because I wanted to go for broke since it was senior year. Luckily, I started to overtrain again but caught it before it got bad(and early in the summer), and was able to get it to consistent 60 mpw for the first time ever after only being able to cram in 3 60 mile weeks in a row before. Including xc and summer I had about 3.5-4 months of 58-65 mpw with easy days usually 740-755 pace(easy days now usually 720 pace so I might be in better shape now).
That xc season we raced almost every week and did lots of 5k pace work and did a short easy 6x800m with 2 min rest cruise interval workout every week. Also taking the advice of my 909 2 miler friend, I learned patience and learned how to properly pace and use surges in races which made me improve a lot. After running 1819 as a junior and 1744 as a sophomore, I lowered my pr to 1653. My track prs are 220 800, 448 1500, 1026 3k(although I split 1002 at the END of a 5k during senior xc), all from my sophomore year. Didn't do senior track cuz my coach started me on workouts too early and I peaked over spring break before we started racing and then I needed a 2 week break and missing 2 weeks of practice and just showing back up would look bad to the team so I was kicked off the team.
This summer, that not-smart over-ambitious HS mind set kicked in again and after reading about Frank Shorter, Amby Burfoot, and Bill Rodgers I upped my mileage drastically. I did it too quickly and went overboard. I even did a 140 mile week and 5 straight weeks between 120-140 after 2 months at 90-95 mpw. At least I know I can do that mileage now, but much more than 90 isn't fun, and I need to train smarter.
I realize now that throughout HS I took shortcuts, and they didn't work out well. The only time I trained smart was my senior year xc and it was easily my best season. From now I want to train smart and take no more short cuts. I have a very long time to get back up to 90-100 mpw since I don't want to do marathons until 24-25, maybe 22-23 at the earliest.
Here is my weekly structure now in terms of mileage by day Mon-Sun: 8-10-12-8-10-12-rest. I do 10 strides after Monday run and 3-4 30m sprints after Thursday run. I'm going to start workouts next week with some cruise intervals once a week on Tuesdays(totaling 10-11 miles counting warm up cool down and recovery jogs) for a few weeks. Then start 2 workouts a week.
If you're interested in coaching me, just leave your email and I'll email you.