well, there\'s too ideas about "bulking"
One is the basic idea of bulk and cut, where you build muscle and take acceptablel fat gains, then cut off the excess fat with acceptable muscle loss.
Then there are caloric cycling (refeeds)
This is when you have one day a week of overfeeding by about 500 calories of carbs. The idea is that our weight and appetite is controlled by leptin levels. When we diet, the leptin levels lower, and fat storage becomes easier and appetite raises. By a controlled overfeed, leptin levels raise and this lowers appetite and raises baslar metabolic rate.