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How does the body utilize calories? If you said that calories are expended or stored as energy, you're on your game. Our goal is to clarify how energy is expended to help each bodybuilder plan his or her
diet in order to minimize the storage of energy as fat. There are three ways in which the body expends energy: basal metabolic rate (BMR), physical activity (PA) and the thermic effect of food (TEF). Total
energy expenditure (TEE) is the sum of these three components.
These components comprise the energy expenditure needed for physical movement, for the body's ability to maintain its normal functions (breathing, heart beat, body temperature, etc.) and they allow for the generation of tissue during growth and repair. Does this make a case for the legitimacy of calorie counting? Absolutely. Every calorie ingested will be either expended or stored. No matter how healthful your diet, if more calories are consumed than burned, you will gain weight. Likewise, if you're taking in fewer calories than you use, you will lose weight.
As weightlifters, we're very familiar with carbohydrates, protein and fat, and many of us are accustomed to counting grams, so let's take this basic knowledge and convert grams into calories as follows: Many people follow a high-protein diet using a guideline such as: one gram of protein per pound of bodyweight. On this diet, a lifter at 220 pounds would have to ingest 880 calories of protein daily.
Now that we've had a short lesson on calories, let's get back to our evaluation of energy expenditure. In order to accurately adjust our diet for maximum output, we need to know how these ingested calories are utilized. We will begin with the component that has the highest demand for calories -basal metabolic rate. The BMR is the amount of calories ex-pended, or burned, during a 24-hour period of absolute rest. This expenditure provides the energy for the normal function of the lungs, heart, cell repair and maintenance, and body temperature regulation. Slightly important, don't you think? It accounts for 60 to 70 per-cent of an individual's energy expenditure.
The BMR is determined on an individual basis depending on one's weight and overall body composition (lean tissue-to-fat ratio). The more muscle mass the higher the BMR. This is what allows lifters to ingest so many calories without packing on fat. Unfortunately, this can cause a large grocery bill-to-muscle ratio as well. I guess we will have to choke down an extra steak or two.
Next we discuss the calorie expenditure of physical activity (PA). This is our most imprecise measurement because we must rely on estimates. When we talk about PA we mean every movement made that expends energy, including every menial task done - even tooth-brushing. This is the component that burns the second-highest proportion of calories, with an expenditure range between 20 and 30 percent of total energy output.
We know how to figure the BMR, which accounts for roughly three-quarters of energy expenditure. Now we need a way to figure out a value for PA. Because caloric expenditure varies between physical activities, it is necessary for us to find an estimating system.
We are going to use the MET system to solve this dilemma. What the heck is a MET? The MET (metabolic equivalent) system is nothing more than an easy method of estimating the intensity of physical activities. One MET equals resting oxygen consumption - 3.5 milliliters 02 per kilogram of bodyweight every 60 seconds. When walking quickly you might use six METs, you might use 20 METs when running. Because the amount of energy used performing any task is directly proportionate to the amount of oxygen used, this is a good indicator of caloric expenditure.
Moderate to strenuous exercise also has a thermic effect, in which calories are burned after exercise completion because of an in-crease in metabolic rate. Also, the greater one's bodyweight, the higher one's energy expenditure will be. If this all seems too complicated, relax. It is as easy as referring to an American College of Sports Medicine (ACSM) chart and looking up any activity's MET value. You may even find this information on the Internet or on the piece of equipment you are training with. Okay, you have your MET value. Now what? How many calories are you going to burn? Glad you asked. Grab your calculator. Once you have your MET value, plug it into the following formula for calories burned: calories burned - MET x bodyweight in kilograms (1 kg = 2.2 lbs.) x time in hours (a half hour would be 0.5). Remember, these numbers are still estimates, with a margin of error of a few percentage points, but they're close enough for our purposes.
The thermic effect of food (TEF) is the energy that it takes for your body to transport, store, absorb and metabolize the food that you ingest. The significance is that a person's TEF can burn 10 to 12 percent of the ingested calories. This process takes place in the first couple of hours after a meal, and is based upon the fact that each particular food has a certain thermogenic effect. Important stuff. This may be one of those dietary tweaks you're looking for. What is interesting is that the TEF varies according to types of calories taken in. Calories from protein and carbohydrates are known to have a higher TEF than calories from fat.
Pop quiz: You ingest 4,000 calories. Roughly how many of these calories will be used for TEF? Four hundred is correct. I know this was borderline insulting, but I just wanted to clarify that our formula is to multiply the total caloric intake for the day by 10 percent (total calories x. 10 = TEF).
Application of what we have learned can help us determine our caloric needs and expenditures. During a building phase we can look at the amount of calories taken in and figure what is available for increasing body-weight and size. On the flip side, during a cutting phase we have the ability to monitor and adjust the percentage of calories taken in from protein. By having the ability to account for total caloric expenditure during a 24-hour period we can mathematically figure out the necessary caloric intake for achieving our goals, whether building. cutting or maintaining.