Some veteran muscle-builders claim that you cannot build muscle and drop body fat at the same time, while others will say that it's just really hard to do.I belong to that second camp. If you want to bulk up quickly, it's VERY difficult to lose body fat at the same time.
However, if you're in the slow-growth mode, you certainly can build muscle and lose fat simultaneously.
When trying to bulk up, the common suggestion is to go on a "see food" diet - if you see food, eat it. And if you don't see food, go find some!
This is all well and good, but many weight trainers, desperate to build a muscular body, go overboard and forget that once you gain fat cells, you CANNOT lose them; in fact, you can only make them smaller (short of liposuction, of course).
The rule of thumb I live by is to watch your abs. If you begin to lose definition in your 6-pack, then cut back on the food stuffing for a few days and up the cardio workouts. No one every hurt themselves by adding 15-20 minutes of cardio.
Of course, if you're in a growth phase, you'll want to refrain from any cardio work. But growth phases really should last only 3-6 weeks, then followed by a maintenance, or "cutting up" phase (also of short duration).
If you don't have the luxury of a 6-pack that you can watch, you can still watch your waistline and see if you stop progressing in that department. If you have, simply add in some cardio and cut the calories for a few days.
You can also use a tape measure to gauge your progress. If your waistline is getting smaller, you can rest assured that you are losing body fat, especially if you're a guy. Gals tend to lose the body fat in different areas first.
So, to sum it all up: It is possible to gain muscle and lose fat at the same time. It's just really difficult.
If you want to see how a professional bodybuilder does it, check out Tom Venuto's Burn the Fat Feed the Muscle.
