There hasn’t been much research done to answer this question.
Many marathoners who feel the urge to don their trainers a few days after their 26.2-mile race wonder when’s the right time to resume training.
Is it one week? Two? Four or more?
How about the old advice to take one day off for every mile raced?
The New York Times’ Gina Kolata tried to find out the answer to this question, but unfortunately it isn’t so clear.
Exercise physiologist Dr. Tim Noakes says the days-for-miles formula hasn’t been proven. “The days-for-miles recovery theory was popularized in the 1970s but was not scientifically based,” he said.
Another physiologist, Hirofumi Tanaka, admits the recovery question is a “tough one.”
“The answer will be dependent on what element of recovery you are interested in,” he said. “We do have some information about how long it takes to replenish muscle glycogen, the primary energy fuel during strenuous distance running. But we have no idea on other elements.”
For More: The New York Times