There is a big difference between walking on a treadmill and walking on a treadmill at peak incline. There is a strong argument to be made that if you put a treadmill on #15 and power walk it for 1 mile it will be as difficult (or more so) then running a mile at a regular pace.


If you've ever hiked a mountain it can be pretty brutal going uphill for extended distances. Even at a leisurely pace.





Some humans (Certain tribes in Mexico and African tribes) have mastered the art of endurance running. Literally running down an animal until its too tired to continue then harvesting it up close. Humans are certainly capable of running extreme distances.



But I do agree walking long distances with short sprints/bursts of speed is most likely the idea for health and over-all athleticism. There is a reason why most marathon runners look like ****. Aside from Cameron Hanes I can't think of any other long distance runners that actually have a decent physique.