cant believe some retards on here. why do you think our brains use carbs as energy, and that our muscle use glycogen (carbs) as energy too? wake up. btw, i tried it, just to see what it did, and it sucks. no energy, FLAT like pancake, only thing its good for is to get a ripped face fast!
You're right, the brain and our muscles naturally fuel on glycogen but they will switch to relying on Ketones when glycogen isn't present. Most all guys who have a serious lack of energy on a keto diet do so because they're not taking in enough good fat. While most any diet below 50g of carbs per day is technically a keto diet if it is not high enough in fat to meet your daily needs you'll feel like absolute crap. However, if enough fat is present, although your energy won't be spiked it will be even and constant.
As far as the flat look, yes initially this will be true but if you stay on a good keto diet long enough and get lean enough you'll notice your muscles will start looking fuller and on the days you do eat carbs you'll notice the full look you obtain last much longer from one simple meal of carbs than it normally does.
I'm on keto right now its great for shaping up. I have an all carb meal once every 10 days which is 4 donuts and ice cream. This seemed to stop my legs and arms going skinny but still loose fat. Haven't shit in days though
A very common problem for some guys on a keto diet, that's why most need a good fiber supplement. Besides, a good fiber supplement is a good thing whether you're on a keto diet or not as it helps keep you flushed out and just simply feeling better.