ketosis is when your body uses itself for energy. as long asyou dotn do anything strenous, your body will burn fat while in ketosis. if you are doing anything physically active, your body will use muscle during ketosis. so as long as you eat carbs before you workout, you will be burning fat al day and all night, esxcept when you are lifting...thats when you are tearing down the muscle. you CAN build muscle while in ketosis, just eat enough healthy fats and proteins. because those are what build muscle back up, not carbohydrates. they only provide energy.