Energy balance is the basis of weight management. Do you want to lose weight, put on a few pounds or stay right where you're at? Whichever scenario you are in, energy balance will get you there. Energy balance is simply the amount of calories you eat versus the amount of calories you burn. The result will be either weight loss, weight gain or weight maintenance.
The equation: eat less calories than you burn. This simple equation has two parts; the amount of energy (calories) you eat and the amount of energy you burn. The larger your calorie deficit (difference between amount of calories you eat and the amount you burn) the quicker you'll lose weight.
When you burn more calories than you eat, your body will be forced to look for the energy it needs in places other than food. For example if your body is burning 2,200 calories per day and you only eat 2,000, your body needs to find that 200 calories somewhere.
Your body typically uses (burns) stored energy in the form of fat to make up that calorie deficit. If you create a calorie deficit over a long period of time, your body will eventually start to use noticeable amounts of body fat for energy and you'll start to see progress.
If you want to lose weight you can either eat less, exercise more or a combination of both. Combining the two will give you the best chance to succeed long term. Without doing both exercise and diet, you'll have to make more extreme changes to the one side you're working on.
Gaining weight also has a simple equation though the process is a bit more complex if you are looking to only gain muscle. Gaining weight requires two steps: 1)eat more calories than you burn and 2) be engaged in a strength training routine.
When these two rules are followed, your body will take your calorie surplus and use it to build stronger and bigger muscles. If you don't have a strength training routine, your body will take the excess calories that you eat and turn them into fat. Instead of getting muscular, you'll get fat.
If you don't want your weight to go up or down, you need to eat roughly the same amount of calories that your body burns. If your body is burning 2,000 calories a day and you're eating 2,000 calories a day, your body won't have to draw on fat stores for energy and it won't store excess energy that you are eating as fat. Your weight will remain the same.
Counting the calories you eat is one thing, but how are you supposed to know how many calories your body is burning. Short of renting an expensive laboratory and testing your body, all you can do is estimate using formulas designed for the general population. You can find calorie calculators all around the internet which use the Harris Benedict formula to estimate how many calories your body burns based on your size, gender, age and physical activity level.
When you get an estimation from one of these calculators, use it for two weeks while monitoring your weight. If your weight isn't going in the direction you want it to, adjust your calorie intake accordingly. Increase/decrease it if you want to gain weight faster/slower or decrease/increase it if you want to lose weight faster/slower.
The Bottom Line
Weight management is a game of numbers. While there are plenty of products that promise to help you gain muscle or lose weight quickly, any plan that promises to produce results without hard work and dedication on your part is a waste of money. Proper diet and exercise is all you need to reach your goal.
The Bottom Line
To build any sort of structure, you need a form of energy and building materials. Your body works in the same way. If you want to gain weight in the form of muscle, you need to stimulate your muscles through strength training and give it enough nutrients (both energy and protein) to grow.