When the idea first came to you about bulking yourself up and packing on some muscle I’m betting the image you had in your minds eye was that of a bulky, muscular physique, with low body fat showing off all of those hard earned muscles in all of their glorious definition. You don’t want it covered by a thick layer of fat, do you?
So, you need to learn how to build lean muscle, and avoid fat as much as possible. I say avoid it as much as possible simply because, that is the best you will be able to do; putting on fat is part and parcel of building muscle, because you are constantly on a calorie surplus.
That’s why it’s important to forget any ideas about, and to ignore any advice which states it’s possible to build muscle and lose fat simultaneously; it’s not. To lose fat you need a calorie deficit, so naturally, both can’t exist at once. So – you’re going to get a little fat on you frame, get used to that idea right now.
You can bulk for any period of time you choose. Some do it for years on end, while others do it for just a couple of months. My personal opinion is to bulk for at least 6 months, and then cut.
The idea when bulking is to limit the amount of fat you put on by not being careless with your calorie surplus. Heeding the advice of others verbatim isn’t always the best thing to do. Calculate your calorie intake, and make sure you eat around 500 calorie surplus a day. (Calculate by finding your body weights in pounds, and multiply by 15, then add 500 and that’s what you’ve got to eat daily.)
Once you reach a point where you think the fat is getting out of hand and you’d like to cut then simply begin eating at a 500 calorie deficit. This is calculated by bodyweight in pounds multiplied by 15 minus 500.
So remember, yes, it’s possible to build lean muscle mass by limiting fat gains, but don’t obsess over this and stifle your gains by eating only a minute amount of calories over. It’s fat better to get the muscle first, and then deal with the fat later.