> If you're serious about running a marathon you'll probably average about 80km/week in training.
For my first marathon, my training was a half marathon the month previous and my training for that was zero (signed up 3 days before.) Now I'll concede it wasn't fast by any means (5h35) but you absolutely do not need to do 80km/week for marathon running if you're going to be in the 4h30-6h timeframe (and, indeed, most of the extreme runners I know don't do any training because they're averaging 50+ marathons a year and there's just no damn time for anything else.)
I think most people in reasonable, healthy shape can physically cross 42km. I don't mean at all to diminish it as an achievement to complete one in any time, but I think you are minimizing the effort many people put into training. The OP's amount is not an unreasonable weekly target for many people. IMO being "serious" as mentioned above is closer to a 2.5 to 3.5hr finish time.
> I don't mean at all to diminish it as an achievement to complete one in any time
Good.
> but
Oh dear.
> I think you are minimizing the effort many people put into training
Nah. Just pointing out that people who say "you must do 80km a week to run a marathon" are talking gibberish. If they added "sub-3", sure, I'd accept that as probably valid (although I know people who do sub-3 without 80km a week.)
Like I keep saying, it's all anecdata and there's no hard and fast rules yet people insist on pontificating as if there are.
For my first marathon, my training was a half marathon the month previous and my training for that was zero (signed up 3 days before.) Now I'll concede it wasn't fast by any means (5h35) but you absolutely do not need to do 80km/week for marathon running if you're going to be in the 4h30-6h timeframe (and, indeed, most of the extreme runners I know don't do any training because they're averaging 50+ marathons a year and there's just no damn time for anything else.)