Is Your Metabolism High or Low?

by Randell Allen on April 20, 2011

There are four major factors affecting the amount of calories you need (metabolism). These four are the keys to your weight loss success or failure.

What you are about to learn are some of the reasons some people see results right away, while others seem to struggle often spending years jumping from program to program with marginal success.


Muscle Mass- Your METABOLISM, or the TOTAL AMOUNT OF CALORIES YOU UTILIZE IN A 24 HOUR PERIOD is directly correlated to the amount of muscle mass per pound.

The more muscle you have the more calories you burn, thus weight loss may be easier if you have large amount of muscle mass. This is the reason why males sometimes lose easier than females. Men generally have more muscle mass.

The more muscle you have the higher your metabolism.

Example 1:

For example, if you are 150 pounds and 10% body fat, your fat mass is 15 pounds and your muscle mass (total weight minus fat mass) is 135 pounds.

Example 2: 200 pounds * 20% body fat, fat mass is 40 pounds and muscle mass is 160 pounds.

The person with 160 pounds of muscle mass will burn more calories at rest.

Diet History - Usually, when you hear of someone who has lost a lot of weight the person is a first time dieter. Or, at least, the person has maintained their weight for approximately two years prior to starting their weight loss program.

The first time dieter, or the person who has a stable weight for at least two years or more, has yet to activate the natural defense mechanisms, which lower their metabolism.

The first time dieter has a variable grace period of weight loss before defense mechanisms are activated.

Dieting Suppresses hormone activity

Thyroid hormones are major contributors to your metabolism. Dieting reduces thyroid activity. Low thyroid activity means you burn fewer calories.

Insulin – Insulin is the hormone that regulates glucose uptake.  Insulin also produces thermogenesis (heat energy). Dieting reduces insulin activity. Fewer calories are burned.

Catecholamine hormones (noradrenaline) – Noradrenaline is a catecholamine hormone. The catecholamines not only mobilize fat for energy, these hormones are also extremely thermogenic. Dieting reduces catecholamine activity, which reduces your calorie burning potential.

These hormones are key factors in lowering your metabolism. Eventually, suppressed hormone activity contributes to a weight loss plateau.

This is an important concept to understand. When the first time dieter begins a diet and their metabolism is not suppressed, which contributes to weight loss success.

Dieting appears to suppress hormone levels for several months even after the diet ends.

Exercise History - There is numerous benefits to exercise. However, exercise makes your body extremely efficient (heart, lungs, and muscle adapt to exercise).

When determining the amount of calories you need to begin your program, exercise history becomes another important factor.

If you are not exercising or have not exercised consistently your body will not be efficient. This translates into sore and tired muscles with the least amount exercise.

Sore and tired muscles means that many calories will be utilized, not only during workouts but also afterward during recovery.

This is another reason beginners sometime lose weight easier. Not being in good shape can actually be a plus when beginning a weight loss program.

Conversely, someone already in good exercise shape will have to work much harder to create the sore and tired muscle impact needed to stimulate his or her metabolism.

Another potential down for some exercisers is the potential loss of muscle mass. Many exercisers have unknowingly lowered their metabolism by losing muscle by improper dieting. (This can be easily determined by finding out how much weight the person has lost over the last couple of years). If this is the case, this group will have a suppressed metabolism.

Age - Age is placed last on the list for a reason. A common belief is age is the strongest factor lowering your metabolism. Muscle is actually the most important factor determining your appropriate calorie intake (metabolism).

After the age of 25 the average person loses approximately .5 pounds of muscle per year. What most people attribute to age lowering their metabolism is actually due to muscle loss.

Age does play a role nonetheless.

Growth hormone and testosterone stimulate fat loss and muscle maintenance, and both hormones peak at adolescence and decline with age. After the age of 25 diminishing GH and testosterone levels contribute to your metabolism lowering. This is one reason younger people sometimes lose weight faster than older adults.

The best case scenario for beginning a weight loss program

  • First time dieter
  • No previous dieting history
  • Not exercising already at peak levels (several days a week at high intensity)
  • A male or female with much muscle mass (men over 150 lean body mass and women over 100 lbm)
  • Less than 25 years of age

Potentially challenging cases

Yo Yo Dieter

Already exercising consistently at peak levels

Low muscle mass

Over 25 years of age

Yes, these people can lose, their calorie intake will be lower and their adherence to exercise and proper food intake must be consistent due to a lowered metabolism.

What you need to know to be successful long term

  1. Know your body composition or lean mass to body fat ratio (Get tested!)
  2. Get your calories right
  3. Analyze your age, sex, diet and exercise history
  4. Keep a food journal


Wikepedia Basal Animal Metabolic Rate: Retrieved April 15, 2011

Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients) (2005) National Academy of Sciences. Institute of Medicine. Food and Nutrition Board

P. S. SHETTY (1990) Physiological Mechanisms in the Adaptive Response of Metabolic Rates to Energy Restriction Nutrition Research Centre, Department of Physiology, St John’s Medical College, Bangalore 560 034, India 49-74 49

Elliot et al. Sustained depression of the resting metabolic rate after massive weight loss. Am J Clin Nutr 1989;49:93–6

Be Sociable, Share!

No related posts.

{ 0 comments… add one now }

Leave a Comment

Previous post:

Next post: