For runners that have ran both sub 18 and sub 16 in the 5k:
-What was your mileage when you first went sub 18?
-What was your mileage when you first went sub 16?
-In your opinion, would you say higher mileage or better quality workouts made the bigger impact on achieving sub 16 versus sub 18?
-Wasn't keeping a log when I broke 18, but probably ~45 tops.
-65-75 for about 6 weeks, a couple weeks later I broke 16 for the first time.
-Sub 18 was just deciding to take running seriously and doing the workouts my coach said. Sub 16 was all putting in the mileage, as my workouts didn't change much from the prior year other than me getting stronger and running them faster.
I had a 18:33 CC PR but the next year I went 16:34 on the same course. The real difference in training was running only during CC season vs. actually running during the off season. probably 20-30 mpw got me sub 18:00 shape.
60-70 mpw for a few months with a month or two of workouts twice a week and a long run got me to sub 16:00
30 and 85
I was quite young when I first broke 18, so maybe ~25 miles, my first time breaking 16 I was up to about 35 majority were pretty good quality, this was in HS and I focused on the 1500m (clearly didn't like high mileage)
However in Uni I upped things a lit to about 75 miles and ended up low 14's... mileage helps.
The first 5k I ran was 17:12 and the mileage was pretty low about 30-35 mpw.
The first sub-16 5k I ran came after a sequence of weeks running 60 minutes per day. The mileage unknown because I ran how I felt most of the time, did fartleks three times per week and twice ran short interval workouts.
There is no magic number to attain a certain fitness level. Most importantly, I could do 10 pull ups from a hanging start (forward or backwards) when I was in sub 16 shape.
First did sub 18 37 years ago in what was my debut:
17:45 - at about 40 miles a week
It took six years but smashed PR 45 seconds, running 75-85 mpw to go 15:30. After that I broke it every year for 8-9 more years, but usually in the 50 mpw range.
As far as mileage it's not either or. You need both. Volume for at least part of the year and then some quality work to sharpen, callous, and prepare your body (and mind).
Sub 18: 40 MPW, was a sophomore in high school and did it on the track.
Sub 16: Consistent 75 MPW for about 9 months leading up to it.
Honestly they were so far apart it was a combination of both mileage and better quality workouts. Before the sub 18 I had never run further than 11 miles and on average a long run was about 1 hour (8ish miles). By the time I ran sub 16 I was doing 14-15 mile long runs each week. I also was going from 3 miles worth of workouts to 5 miles of distance in each workout.
First time under 18:00 - 9 miles a week.
First time under 16:00 - 15 miles a week MAX.