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Boosting Your Metabolism

Boosting Your Metabolism

(2 of 2 pages)

How can I calculate my Basal Metabolic Rate?

Your basal metabolic rate (known as BMR) is the energy it takes to keep your involuntary body processes going.

About 60% of the calories you consume are used for such things as breathing, maintaining body temperature, manufacturing hormones and keeping your heart beating. It takes roughly 10% of calories per pound of body weight to meet those needs. A 120lb (8st 8lbs) woman, for example, will need 10 x 120, or 1,200, calories each day just to function. So at 144lbs you would need 1,440 calories.

It is then important to keep in mind that many factors can affect your BMR:

1. For every decade beyond the growth years (about age 20), for instance, your caloric needs drop about 2%. A 30-year-old may need 1,200 minus (2% x 1,200) = 1,176. So, you would need to calculate your age percentage and deduct it off 1,440.
2. Your body build, which is largely inherited, is another factor tall, thin types burn more calories because they have a larger surface area, and more calories are burned to maintain normal body temperature.
3. Muscle burns calories, even at rest, and men, on average, have more muscle than women, so they too need more calories.

How can I affect my BMR?

There are ways to affect your BMR so take the following into account:

Exercise: Depending on the length and intensity of your exercise, you can boost your BMR for several hours afterwards.

Diet: Severe dieting can reduce your BMR as your body attempts to conserve calories. This is a survival tactic and not a good idea for a healthy lifestyle.

Increased muscle mass: Muscle burns more calories, even at rest, than fat. The greater your ratio of lean to fat, the more calories you will burn.

Calorific needs: About 30% of your calories fuel any physical activity you do, from scratching your nose to running a marathon. Of course, the marathon will take significantly more than an additional 30%.

How do I calculate my daily calorie needs?

To figure out how many calories you need to add on for your level of activity, multiply the calories needed for BMR by the percentage that matches your activity level.

• If you're sedentary (mainly sitting all day), multiply by 20%
• If you engage in light activity (such as walking to and from the bus stop, cooking dinner, etc) daily, multiply by 30%
• If you do moderate activity (very physically active - little sitting, heavy housework and gardening), multiply by 40%
• And multiply by 50% for very active (construction work, and active and prolonged physical sports)

About 10% of your calorific intake goes for fuelling digestion and absorbing nutrients. To determine your caloric needs for this, add the calories for BMR and the calories for physical activity, and then multiply the total by 10%.

To calculate you total daily calorific needs...

Now add up the calories for each purpose to determine your total energy needs:

Calories for BMR

Calories for activity

Calories for digestion =

Calories for all your energy needs

One pound equals 3,500 calories. To lose weight, you need to eat 3,500 calories less for each pound you want to lose or increase physical activity while maintaining your current level of eating (or a little of both).

While this is a mathematical way to calculate your daily energy requirement, the best way to figure the number of calories you need is to tune in to your body. Listen for signs of hunger or fullness, not only in what your stomach says, but also in how you feel and how much energy you have.

The more you listen, the better you'll hear. Combine what your body is telling you, what the books and maths are telling you, and come to your own conclusions about how much you need to eat. Then enjoy those life-giving calories for all they're worth.