Remember when you were young and your mother was constantly reminding you to stand straight, keep your head up and shoulders back? While it seemed like nagging back then, your mother was only doing what was best for you: encouraging good posture.

There's nothing bad about good posture. According to Dale Greenwald, a nationally recognized exercise physiologist and owner of BetterPosture.com: "When the body is properly aligned, everything functions better. Your organs are in a position for optimal performance.

"Digestion is improved, which can result in weight loss," says Greenwald. "Energy is increased, helping you burn more calories in your aerobic activities. Breathing is easier, so oxygen is getting to where it needs to go."

Proper posture also positively affects your biomechanics, helping you move more gracefully and efficiently. Believe it or not, it makes you look slimmer and more confident, too. It's one of the quickest and least expensive ways to improving your entire appearance and quality of life.

On the other side of the coin, poor posture can negatively affect your health by putting unnecessary stress on your entire body from top to bottom. Unfortunately, in our busy daily lives, everything we do is pulling us forward out of good posture whether it be sitting at the computer, driving in the car or cooking at the stove. But there's an easy way to fix that.

According to Greenwald, it's a matter of using three easy-to-follow posture principles:

1. Uplift your sternum while rotating your shoulder blades back and down. Where your sternum goes, your head and shoulders will follow.

2. Align your pelvis and engage your stomach muscles.

3. Elongate and center your head and neck over your spine.

When applied daily at work, during exercise or as a part of everyday life, Greenwald says that these simple steps will change the way you look and feel.

So think about standing tall and your body will thank you.

Rebecca Heaton is a sports and fitness writer and editor of the Rocky Mountain Sports magazine based in Colorado. She also contributes to a number of other regional sports and fitness publications around the country.