Marathon on 10K training

Not the worst idea I've ever heard, especially if you feel like you've plateaued. Mix it up, try something different. I'd want to make sure that I got at least a couple of quality long runs in though...16-20 with some race pace miles in there.

Why not try it? I trained for 10K for a few years (ave about 60mpw) then got talked into doing my first marathon 6 DAYS before the event! I ran fine: a my-10K-equivalent time (2:25). Previously had never run further than 15miles. Caveat.....I was 23yo, and had 10 yrs of running under my belt. Still, just shows that some people do not need specific prep. to marathon.

Back when I was a "real runner", I always seemed to run my best marathon right after ( 1 to 2 months) XC season; back off on the intervals and throw in a couple of longer runs of 20+. So if you feel you've stagnated, I would definitely suggest taking a shot at something different, and your idea seems reasonable.

That´s how most marathoners trained in the 1970s/80. They basically did 10k training with a longer long run.

I think you can with 1 longer run at marathon pace 8-10 miles each week.

I ran the New York City Marathon predominately on (10k stuff) mile repeats etc. and ran to 2:36...

Super low mileage and mainly fast hard stuff..... and some cross country meets .....I was 38 years old with not a massive base of running behind me.

I then trained much more specific for the marathon ....for a full six months build ....and only ran 233 at Boston..... I still ran pretty low mileage but much more marathon specific runs and distances. I was sort of surprised there wasn't a massive difference in time or race day feeling....I felt way more prepared for Boston but I wasnt shockingly faster. I would say I did double the preparation for Boston that I did for New York City and the return on investment was only three minutes.

I think it's totally possible to run a strong marathon off 10K training assuming you have pretty good muscular endurance hopefully from some other sport like Cycling or Nordic's game etc I think it's totally possible to run a strong marathon off 10K training assuming you have pretty good muscular endurance hopefully from some other sport like Cycling or Nordic skiing. I would say for sure at least personally..... 10 milers at pace pretty damn regularly (weekly) would have to be a staple included....or you'll crack up 13 to 16 miles.

Yes, it seems like a logical direction for training ..but like anything that is bound to work it will probably be best to integrate the greater intensity ( 5 X 1 mile /8 X1km, etc) gradually and take as little away from the quality and length of long runs. You say your 20 milers are easy, so why not see if you can manage them with more track work slowly added on. You know what works basically for you so it's more about tweaking than reinventing the wheel..

Another thing you could tweak is integrating some pick-up miles during the longer stuff, maybe 2-3 of them seperately at 10 seconds/mile faster than marathon pace. It might be enough to stimulate improvement... for your first sub 3 ..

35 is still very early in the marathon game, so worry more about training than your age for sure..good luck !

When I trained with Deena Kantor and Keith Brantley that's exactly what they did.