I've heard this topic discussed quite a bit on podcasts that I've been listening to. If you are LCHF and are looking to be a serious athlete or even just be active for the rest of your life, this is a good topic to look into.

Check it out this podcast -
Metabolic Flexibility, Insulin Sensitivity, Macros and Ketosis w/ Dr. Mike Nelson
http://daily.barbellshrugged.com/episode223/