Building muscle requires you to train with intensity, lift progressively heavier weights, and eat a diet rich in protein and calories. While everyone is able to gain muscle naturally, people will differ in the rate they gain muscle. And the amount of muscle you can gain in a year will be influenced by several factors such as genetics, intensity, consistency and diet.
Your genes play a huge role in how much muscle you can gain in a year. According to strength and bodybuilding coach Christian Thibaudeau, one of the major factors in gaining muscle is the ratio of fast twitch to slow twitch muscle fibers you have. Fast twitch fibers have a far greater potential for growth than slow twitch fibers -- and your ratio of fast to slow twitch fibers is predetermined by your genetics. The size and shape of your muscles will also depend on where they originate and insert, which again comes down to genetics.
There is no best training program, and it is possible to build muscle on any strength training and resistence routine provided it is balanced, meaning it works each muscle group an appropriate amount. Use barbells, dumbbells, kettlebells or machines at the gym for a workout that supports your goal of gaining muscle. The majority of your focus should be on large muscle groups such as the legs, back and chest -- and smaller muscle groups like the arms and calves should receive less emphasis. However, whatever routine you follow, the amount of muscle you gain will be down to how much intensity you put in when you train, how consistent you are with your sessions, and whether or not you strive for constant improvements.
Diet is an often overlooked, yet an extremely important part of gaining muscle. In order to repair and grow, your body needs plenty of calories and protein, as well as fats to help with cell and hormone production, and carbohydrates to provide energy and improve recovery. Carbohydrates in fact, are the smartest fuel you can consume; even more than protein. While protein is necessary in the repair of muscles, carbohydrates give you the energy you need to perform the exercises. You only need about 1.5 g of protein per pound of body weight every day, and the rest of your calories should be comprised of healthy fats and carbs. If you fail to take nutrition seriously, your muscle gains will be severely hampered.
How Much to Expect
It is not a good idea to set yourself a specific amount of muscle to gain in a year, as the above factors all independently play a huge role in how much you will put on. You may have the best diet in the world, and train as hard as you can, yet if you have poor genetics you may only put on five or six pounds of muscle in a year. Likewise you may follow a very poor training routine and diet, but have excellent genetics, and gain 30 pounds. Keep in mind that age and gender also impact how much muscle you can gain. Women with a mesomorphic body type is more likely to build muscle than a more slender ectomorph. Women may be able to notice a 20 to 40 percent increase in their muscular strength over several months with strength and resistance training. The best thing to do is to train hard, eat well, aim to constantly improve, and add as much muscle as you can naturally.