How does this work for combat athletes?

Hey all. I run a lot and do Muay Thai. I tried eating only meat and eggs and organ meat for a week and had virtually zero energy in the gym after a few days. Anyone have any advice or can you point me in the direction of something to read about this? Specifically for fighters.

from Zero Carb Zebras http://bit.ly/2ETgeHl
via IFTTT