Hi, Terry! Well, of course there is a considerable number of calories in fat, generally 100 per tablespoon, and the Atkins eating plan encourages its consumption alongside the protein. Fat for fuel and protein to feed muscle so that there is no danger of the body breaking down muscles as the body becomes leaner. Calorie counting and portion control are not addressed as such, except in later phases where using smaller portions of higher-glycemic foods is discussed. The objective of Atkins is simple, to reset the body to burn fat, and thereby to use the body's stores of excess fat as fuel. Weight loss, and lean muscle preservation. I did lose 10 pounds of body fat and gain 12 pounds of muscle in my first 6 weeks of weight training and cardio and was doing great until I injured my shoulder in the gym. :( But I don't know much about bulking up, sorry. A cursory google search I just did showed differing opinions on the ability to do this with Atkins, with some suggestions from those who say it can be done.
Good luck all!
Marie