Energy balance - the amount of food that you take in compared to the number of calories you burn - is perhaps the most vital component of living a fit, active, healthy lifestyle. Consume too many calories without enough activity, and you gain weight in the form of increased body fat. If you don't consume enough calories, you will not have the energy to support the physiological adaptations to exercise, or more simply put, muscle growth.

Last week I talked about safely cutting calories through simple, sensible food choices while increasing one's activity level by a moderate amount to eliminate 500 calories a day and lose one pound per week. For basic weight loss, this is the best approach to help retrain the body's metabolism and ensure that one eats enough to sustain a certain level of activity. But what if weight gain is the goal? If someone wants or needs to build muscle mass, she needs a caloric surplus.

The old adage, "you can't have one without the other," applies to many things: Peanut-butter and jelly, love and marriage, and in the fitness industry, diet and exercise. But for some reason, there are people out there trying to split diet and exercise apart, claiming that one can either eat anything so long as they burn enough calories, or that if you eat specific foods in specific proportions at specific times of the day, you will never have to break a sweat again in order to lose weight.

Well, OK. You CAN lose weight by either increasing caloric output or decreasing your intake, but is losing weight synonymous with being healthy? What does that number on the scale mean, anyway? Let's take a look at a few physiological factors that impact what your true healthy weight range might be.

Since I started my own fitness journey, I have maintained a philosophy that when it comes to dieting, a "diet" is never the way to go. Having spent a year in Germany and time in other European countries, not to mention having worked in Spanish, Southern, Steak-house, and Italian restaurants, I have had way too many amazing plates to ever want to deny myself delicious foods.

Restriction has never been my thing. Rather, when I knew I had to make some changes to improve my overall health, I decided the best way to do it was to look at what I needed to add, not what I had to take away. Looking at the recommendations for fruit and vegetable servings alone from the old food pyramid, I realized that if I met my daily requirements I would simply be too full for a lot of the other junk I was eating at the time.

The food pyramid has changed over time, which can get a little confusing.