https://www.wired.com/2017/02/nike-two-hour-marathon-2/great quick read .. TLDR, no back to back hard days, and on the light day after a hard day, recovery runs are crazy slow ~5 min/km... 20km total that day, 2 x 10 km.
also, kipchoge usually rests 5 days before a marathon.
"slowly by slowly"
A good day of training was worth little on its own, but a good month was worth plenty. Slowly by slowly, the athlete’s shape came. “Every session is a building block,” Sang said.
Valentijn Trouw, Kipchoge’s Dutch manager, told me something else interesting: He thought Kipchoge never killed himself in training. The only day on which he would drain every resource he possessed was on race day. “Never 100 percent in any session,”
“Work hard,” he said. “But not every day.”
the first article, also nice:
https://www.wired.com/2017/01/think-exercise-hard-try-training-like-nike-super-athlete/Before a few months ago, Kipchoge had never run on a treadmill, had never undertaken a VO2 max, lactate threshold, or running economy test, and had rarely worn a heart-rate monitor. Kipchoge’s technology-light approach is the norm among East African marathoners, in my experience. When I stayed in Kapng’tuny, where Geoffrey Mutai and the marathon world-record holder Dennis Kimetto trained in a large group without a coach, the program was set by senior athletes, and workouts were meticulously recorded, by hand, in exercise books. Indeed, Kipchoge has a book containing 14 years’ worth of workouts stored this way.