Originally Answered: muscle gain weight gain help confused?
Gaining weight & muscle is a two step process: you have to eat more and lift weights or engage in some sort of strength training routine.
The most important rule to remember if you want to gain weight is to eat more calories than you burn. Only by doing this can your body use the excess energy to build muscle. If you eat less than you burn, there is no way to gain weight, it's as simple as that. Your first step is to figure out how many calories your body burns per day. Use this calculator http://calorieneedscalculator.com to get an estimate. Now eat more than you burn and you're on your way to gaining muscle.
Gaining weight is as simple as eat more than you burn but if you want to gain muscle, you also need to exercise. If you just ate more without lifting weights, you'd just gain fat and become unhealthy and overweight. When you lift weights (or participate in any strength training) you're actually causing some damage to your muscles.
When you rest, your body uses those extra calories to repair and rebuild the muscles. When this process is complete, the muscle is stronger and a bit bigger than it was before. You obviously won't notice a difference right away, but over time you will find yourself becoming stronger and bigger.
You need to keep your diet clean to gain the right kind of weight. Stay away from sugary and simple carb foods such as candy, foods made with white flour, soda and other junk. These foods will promote fat storage, something you don't need. Stick to foods made from whole wheat flour, oats, brown rice, lean sources of protein (chicken, some cuts of beef, fish), nuts, beans, legumes and protein shakes - yum yum. If you need more details, go to the Straight Health Forums - http://forums.straighthealth.com