As a beginner, your body will be able to create neural adaptations so quickly that you're able to recover from your workouts much faster than an elite lifter. This is why frequency is key to someone new to lifting and acquiring "noob gains". Veteran lifters envy the time they use to be able to lift their 1 RM and go on to work out with peak performance the next day.

At this time, if you're eating at a deficit, eating a large amount of protein (more than if you were simply bulking), and giving yourself enough rest - you can lose body fat while gaining muscle mass. This is called recomposition.

Outside of the very beginning phases of lifting, recomposition is next to impossible or at least extremely slow for progress. A good example of people who do this are people who's career depends on staying very very low body fat percentage year round (unlike Bodybuilders):




The only way to successfully maintain your muscle mass while losing bad fat is to do it very very slowly. The reason professional bodybuilders can hang onto 270 pounds of muscle at 5% bodyfat is because they take drugs that have anti-catabolic properties, meaning your body preserves your muscle from breaking down.

Hope this helps.