Fat is not used for energy which is why its so hard to lose.
Muscles only use carbohydrate simple sugars the glycogen in your muscles.
When you train on super low carb diets you will burn your muscles out which are being converted to sugar to feed your movement because you haven't given any to the body to use, and in that process called KETOSIS you will also burn some fat which was also converted to sugar in a more difficult process.
Majority of fat when it is burned at a super low rate, is expelled from your mouth as carbon dioxide. Your brain and other muscles dont use the fat at all, only GLUCOSE is the fuel they use.
If you train with no carbs in the body you will feel like shit in KETOSIS, this is the basic Atkins diet model of eating Fat and Protein and no carbs. And by the way Dr Atkins was always Obese, and died of heart disease and blunt force trauma to the head after suffering a heart attack and collapsing and bashing his head.
Protein is found in abundance in plant based foods and especially good fats like Omega 3s which are the best for you, along with Iron in things like Legumes and Beans.
This Atkins Ketosis diets along with The SAD diet (Standard American Diet or Standard Australian Diet )is whats causing the heart disease and diabetes epidemic.
Eat plenty of fruit, veg, and water and get some carbs in don't be scared. Live life and respect life.
Check out Dr Barnard how to cure and prevent diabetes. Dr McDougall, The World Health Organiztion (WHO) Dr Michael Greger(How not to die book), Dr Esselstyn. and T. Colin Campbell of the China Study. There are many more examples.
These are my opinions based on science I have learned and Im sharing my thoughts for anyone interested in the real science behind diet related illness. Please do your own science based research.
Dont listen to bro science bodybuilders and shit like that only care about fast results and aesthetic gains in the gym.
A lot of these people eat 8 eggs a day and fill up on protein and, and when you look at the statistics most die fairly young usually not making it to 50, of some form of heart disease or failure.
One example for now is well known celebrity bodybuilder and fitness trainer from the Biggest Loser USA Bob Harper, who recently suffered a MASSIVE heart attack, which he was extremely lucky survive as the type of heart attack he had is called the widowmaker. He is 51 and super fit.
Heres an article:
http://www.news.com.au/entertainment/celebrity-life/biggest-loser-host-bob-harper-51-unconscious-for-two-days-after-massive-heart-attack/news-story/0fed2b6e33b771070a121044c770bf36
and video about widowmaker heart attack:
And before his heart attack heres a video of him on a cooking show giving his advice to people to consume the thickest most unhealthy animal fat in coffee (Also known as the BULLETPROOF coffee) to lose weight, basically keeping you in a constant state of sickness, starvation and ketosis, it works but you will get disease and heart attacks too:
Why you ask?? For those aesthetic gainsssss and heart attack gainsssssss.
Rest my case.
Oh and Bob Harper, RIP if you continue that diet my friend. Peace out.