Question: What does the term metabolism mean exactly, and what influences how well it works?
Metabolic rate is
influenced by six factors
Answer: Metabolism refers to the body's chemical and physiological processes that provide energy -- energy to do everything from thinking to breathing to running a road race.
Your metabolic rate is the speed at which your body burns calories. The higher your metabolic rate, the more efficiently you are getting energy to your cells, and the more calories you're burning.
As we all know, burning more calories means you can eat more without gaining weight.
Metabolic rate is influenced by six factors. The good news is that most of them are at least partially under your control. In other words, you have the power to raise your metabolism, have more energy and maintain a healthy and attractive body weight without depriving yourself of food.
Let's look at the factors that determine your metabolic rate.
BODY COMPOSITION: The ratio of lean to fat tissue in your body is the biggest factor in determining your metabolic rate.
This ratio is commonly referred to in terms of your "percent body fat.'' The lower your percent body fat, the higher your ratio of lean to fat tissue, and the higher your metabolic rate.
Lean tissue includes bone, muscle, organs, blood, etc. We all know too well what fat is. You can change your body composition by gaining lean muscle and bone mass, or by losing fat.
Resistance training adds muscle and bone mass. Aerobic exercise and correct nutrition help you to lose fat.
ACTIVITY LEVEL: Exercise temporarily boosts metabolic rate,when you're exercising and for a while afterward. The longer and harder you exercise, the greater the temporary boost.
You can burn a lot of calories during the period of that temporary boost. Also, remember that muscle is active tissue, fat is inactive.
More muscle means your body is generating more energy. When people tone and develop their muscles they find that they naturally tend to become more active and use their muscles more in everyday life.
DIET: What you eat, how much, and when are all important factors in determining your metabolic rate. In general, eating temporarily raises your metabolism. You've probably heard about the importance of breakfast.
Eating a healthy breakfast containing complex carbohydrates and a low fat protein will "kick start" your metabolism in the morning. But here's a more recent discovery that may go against conventional thinking: By eating small portions of healthy food throughout the day, you can keep your metabolism fired up and can actually burn more calories then by sticking to the three squares that we've always been taught to eat.
AGE: As we get older, our resting metabolism tends to slow down. But this won't happen nearly as soon if you're staying active and exercising regularly. The decreases in metabolic rate with age are primarily, if not entirely, due to the loss of muscle mass and the change in fat to lean ratio.
HORMONES: Thyroid hormone helps regulate metabolic rate. Those with a hypoactive or hyperactive thyroid suffer a reduced or increased metabolic rate. If you suspect thyroid problems, see a doctor.
GENETICS: Genetic predisposition does play a role in determining your metabolic rate, but since you can't change your genes, focus on the factors above that you can influence.
Stephenie Karony is a certified health
and fitness instructor, a personal trainer and the author of
"Body Shaping with Free Weights." Send questions to her at
P.O. Box 262, Wailuku Hi. Her column appears on Wednesdays.