i think several of you hit it. + what "or maybe" just wrote is dead on.
1) Coach B - I agree with...there was a vo2 study + this study was referenced in major running magazine (I believe Runner's World - which at the time was geared more toward serious runners...i seem to remember them citing Dr. David Costill in this article probably 1988'ish.
2) the internet & technology stuff - no, that had not happened yet
3) there was also the Coe et. al. training which was getting some attention (in those days it was said he did about 30-40 miles per week, but very intense circuit style training)
4) some of the big miles runners who had cut back - were getting great results and were crediting the lower miles and better quality. Others would say it was because they first did the higher volume, then the lower milage worked.
Of course i should add we are talking about runners like Fred Tornaden who was the leading American running 2:12 one year maybe 1984 (who had been running 140 dropping down to 100 - 120). So even those guys were not advoacting low, low milage.
I think there is evidence on both sides of this debate and i have done it both ways:
- when i was 10 years old i ran a 10 mile race by training about every other day going 4-6 miles per time at a good steady pace....at 13 my time was 63:01 - this was training on my own, but then
- once i entered hs the coach was an all interval coach....and i slowly watch everyone catch me and pass me by (i did run 9:52 as a junior. but i went from running 10 miles faster than anyone in the state from ages 10-13 to a high schooler who only broke 10 a a handful of times and not by much.
- college (coach was much more Lydiard in style) so i went from running 20-25 miles a week in hs to 70-90 in college. Got better over time. 9:00 steeple; 3:00 1200m relay leg on DMR; 14:56 5,000) but not great
- after college (training on my own once again = meaning i could run my own pace) within 2 years i had run 20K in 1:03 and 8K in 23:45...on 40-45 miles per week (i actually only ran 4 days per week = so everything was fresh and quality = mostly steady states; very few intervals....my typical pace was 5:30'ish sometime faster...typical distance 10 miles sometimes shorter - sometime longer)
- then the running shoe industry stopped making shoe for real runners and added all the bells and whistles (and Runner's World became Jogger's World)...this ruined it for me...i was no longer able to do long runs - so even though i only ran 45 miles per week (i had been doing 10-15 miles per run)...this now dropped to 20-25 with 0 long runs over 10 miles = times got worse i eventually switched over to triathlons to up my volume.
- years later Nike Zoom XC steaks are finally made for minimalist runners who don't like wearing clogs - i have done as long as 30 miles runs...biggest week was 146 miles on 7 runs = so i was doing 20+ per day. Times were getting good for masters stuff.
- of course they no longer make the XC 1's - so i have had to change my training yet again because the xc'2 just aren't the same.
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I have had a lot of running friends who have tried to make a comeback but got injured...my theory is - it may be the shoes...because the shoes we trained in back in the 70 and 80 were nothing like the shoes of today. The old style shoes were quite minimalist in nature - today's shoes are too bulky.
It may also be the speed - they are trying to run too fast too soon without doing enough simple running first.