When I started eating a low carbohydrate high fat (LCHF) diet, I noticed that my athletic performance started to improve once my body made the transition to burning fat over carbs as its fuel source. I had also started Zone 2 training about two or three weeks after I changed my diet. During the first 10 days or so of switching to LCHF, I was extremely sluggish. Not only was my body moving slowly, so was my brain. The sluggishness subsided and the performance improvement started becoming noticeable within a month. I also noticed that my legs did not get the same burning sensations it did when I ran at the faster paces and that my recovery time was cut down substantially! A few podcasts I heard during that time discussed how others eating LCHF had also seen athletic performance gains and had faster recovery times. This totally intrigued me!