Originally Posted by wevie
I guess it's hard if not impossible to get the muscle without a little fat sneaking in there too?
There is no way, one could "exactly" account for the way the body is going to "partition" its calories/macros, and this partitioning can deviate from one person to the next (age, sex, genetics, dietary trend, etc, etc). All personal calorie approximators (like Benedict, and others), are just estimates (though pretty accurate): but sometimes adjustments need to be made cause it doesnt take into account some peoples individual metabolism or one may miscalculate or under/over calculate activities.
Outside of a medical condition, and something the person is not specifiying clearly, in most cases (outside of the genetically gifted young one, roids, and some new to training simulus/dieting to stimulate growth), "most" will gain fat when trying to increase muscle mass. This is why it should be fundelmental knowledge to know your personal calories (to make adjustments), and fundelmental knowledge in how to manipulate the macro nutirients. Then when trouble times come (and they will), you are not holding your d$ck. Instead what you have in your hand is knowledge.
One more thing: Gaining and losing are Energy opposites. To lose a deficit (of some type) has to be created. To gain, a surplus. See the partitioning complication here?