I'm a participant in runner groups. I was surprised to meet several exceptional runners with stories of moving from very unhealthy/overweight to their current level of marathoner+. Several of them had success not just with intermittent fasting, but prolonged fasting. Humans can run when they feel like you have no energy. It's hard to believe that this isn't a psychological and behavioral issue: >A 30 percent reductio…
Ten years after starting to run in this group he was set to run a marathon under 2:50. Unfortunately a cramp around the 30 km mark made it impossible to continue and actually achieve it. But his grit certainly motivated everyone around him, marathoners and short-distance runners alike.
I would love to share his eating habits but I do not remember them in detail and I do not know enough about nutrition to confidently share any presumptions on this part. Your first paragraph simply reminded me of this great individual.