There are a couple examples: Zach Bitter (50 mile - 24 hour races) and Tim Olson (100 mile trail). Both have held notable records. In the marathon distance or

There are a couple examples: Zach Bitter (50 mile - 24 hour races) and Tim Olson (100 mile trail). Both have held notable records. In the marathon distance or shorter, being fat adapted would be a bad thing, as you couldn't train at upper capacities. But where you are running purely aerobically for very long periods of time (12+ hours), this may be an advantage. The secondary (or even primary) advantage would be a low carb or ketogenic diet is that it is anti-inflammatory. People who run ultra distances do huge volumes of training, and it may be enabled by a lack of inflammation.