Marathon plans can be finickity devils.
Finickity. I do like that phrase.
A steady, progressive build of miles is a typical sight on most training platforms presented online or training books. Depending on the individuals ability(beginner, intermediate, advanced) the plan will suggest running anything from 18-24 miles before the big day.
I've been asked the question " do you think I can run a marathon?" quite a lot over the years. My answer has become less abrasive and abrupt however it has always been this.
"you can go out that door now and do one."
I just calculated the average pace per mile we ran the Final Commando Test 30 miler over Dartmoor. 14:40 per mile. 7 hours 20 minutes. In boots, trousers, webbing, rifle, and a wee backpack. Thinking back, the furthest we ran before that was 12 miles. What we had was fitness. To me that was strength, endurance, speed, agility, mindset and power.
Take all the kit off, put the trainers on and transfer the moor for a flat road and I think a sub 4 was within us all for 26 miles. 9:11 per mile.
I'm never surprised by how much emphasis is placed on the "long run" for anyone following a generic marathon plan.
I can't overstate how important speed endurance training , strength training, range of movement, pacing knowledge and nutrition are to the outcome of an endurance race.
KNOW YOUR PACE.
RUN THE RACE.