He was 49 years old. Wouldn't this cause problems for his hips and knees? I'm all for pushing physical limits, but not to the point where it could backfire. Even 20 year-old professional footballers (soccer) are told to take 2 weeks complete rest at the end of a season, and during the season they only train maybe 3-4 days a week.
I hope this guy doesn't regret doing this down the line, because right now it is very inspiring.
After the first 30 marathons, his body has probably settled into a pretty efficient, gentle way to run, out of necessity. There are, in fact, ways to run that put less wear and tear on your body.
It's probably possible to go out in a single day with poor form and do more damage to your body than this guy did in an entire year.
He says about his heart rate that it's "below 100 if I run 10 kilometers". That seems pretty amazing to me. I've been measuring my heart rate recently and mine's at about 150 bpm if I run at a medium pace.
I hope this guy doesn't regret doing this down the line, because right now it is very inspiring.