The right combination Athletes who desire to gain weight should consume extra calories from wholesome, nutritious foods and perform weight training exercises several times a week to ensure the additional weight is muscle, not fat. For starters, try to consume an extra 500 calories a day by eating a larger breakfast than normal, having an extra sandwich at lunchtime and adding some healthy snacks throughout the day. You can also make your own milkshake in a blender by combining low fat milk, a banana and other fruit and even some low-fat yogurt (however, be careful this does not spoil your appetite for your normal meals). Hit the weight room 3-5 times a week to pack on the muscle.
Which type of calories? Your extra calories should be primarily from complex carbohydrates (rice, potatoes, pastas, breads), and secondarily from protein (chicken, meats, fish, dairy) with minimal fat. The carbohydrates will help to fuel your workouts and the protein will help your muscle recovery. Although athletes who weight train need more protein than a sedendary (inactive) person, you can often consume enough protein through a balanced diet of natural foods.
Be realistic Although the above efforts can help you to gain weight, set realistic expectations. If you have trouble gaining weight, it’s because you probably have a fast metabolism, which means your rate of burning calories (even while at rest) is faster than the average person. Consider your parents’ build at your age. If they were thin, chances are you will be too until you get a little older and have put in your time in the weight room and have practiced good nutrition habits.
Don’t go too fast Avoid trying to gain weight too quickly. Doing so can result in the addition of fat weight, not muscle. Strive for an average of a 1-2 pounds a week, and give it time.