To maintain your current weight, the scale needs to be balanced. If you eat more calories than your body needs, you tip the scale. These extra calories are stored as fat -- on your hips, butt, stomach, chest, face, etc., etc. etc. (feel free to add your personal trouble spot here).
To loose weight, you want to tip the scale in the other direction, so that there is a calorie deficit, not a calorie surplus. To lose one pound of body fat, you have to burn (or not eat) 3500 calories.
There are three ways to lose weight:
1) Increase your metabolism. One way to do this is to gain lean muscle (through strength training). For every pound of muscle you gain, your body burns 50 more calories a day. This means that with more muscle you can eat the same amount and still lose some weight.
2) Eat less. To lose one pound of fat a week, you need to cut 500 calories a day from your diet. With 1000 fewer calories a day you will lose two pounds a week. This may sound like a lot of calories. It's important to know that it is.
3) Workout more. If you just exercise, you would have to walk on a treadmill at 4 MPH for 1.5 hours a day, seven days a week, to lose two pounds of fat a week.
The perfect way to lose weight is to do all three.
If you increase your metabolism, eat less, and workout more, you will lose weight. It will be easier and less painful than drastically cutting back on your calories or becoming a slave to the treadmill.
