Basal Metabolic Rate

BMR (Basal Metabolic Rate)
Your BMR, or basal metabolic rate (metabolism), is the energy (measured in calories) expended by the body at rest to maintain normal bodily functions. This continual work makes up about 60-70% of the calories we use ("burn" or expend) and includes the beating of our heart, respiration, and the maintenance of body temperature. Your BMR is influenced by a number of factors, including age, weight, height, gender, environmental temperature, dieting, and exercise habits.

Because of the increased activity of cells undergoing division, the younger the person, the higher (faster) the metabolism. And the taller and heavier a person is, the faster their metabolism. Because of the greater percentage of lean muscle tissue in the male body, men generally have a 10-15% faster BMR than women. Restrictive and traditional diets may cause your BMR to drop as much as 20%. People living in tropical or very cold environments generally have BMR's 5-20% higher than those living in more temperate climates. In general, depending on the intensity and duration, consistent exercise will also increase your BMR.

Note: BMR calculators should only be used to provide a rough guideline on daily energy expended. Actual values cannot be attained using such calculators, and may be quite inaccurate depending on several factors such as geographic location, body-type, diet, body composition, supplementation and some genetic factors. Values which extend +/- 15% above and below your calculated BMR may be a more accurate representation of your actual BMR range as daily fluctuations are constant and your BMR is rarely the same on a daily basis.

AMR (Active Metabolic Rate)
To maintain normal bodily functions, your body "burns" more calories throughout the day than at rest. Once you have calculated your BMR above, you can enter the average minutes you spend in a variety of activities each day. This will help you calculate your AMR or Active Metabolic Rate. Your AMR is is the total amount of calories you expend through different types of activities throughout the day whether it's reading or walking, dancing or swimming. They keyword here is "active" meaning you are consciously aware of your activity. We have divided these into five levels (above) from very light to very heavy and included a few examples of each category to allow you to gauge where a given activity might fit. The result is only an estimate, but should give you an rough idea of your daily caloric needs. Once you've inputted all relevant fields, click the "Calculate" button to generate your daily "Daily Energy Requirement" which is the sum of your BMR and AMR results.

Weight Loss & Total Energy Requirement (BMR + AMR)
Both in theory and practice, weight loss can be as easy as following simple physical principles. You must not ingest more calories than you expend in order to maintain or reduce your body mass. If you learn how to effectively apply this principle to your energy requirements, it is a physiological certainty that you will not gain weight. As simple as this sounds, it is our sedentary society, work environments, poor nutrition and lack of exercise that makes this simple physical principle an extremely difficult and painful process for many.

Many people concerned about weight loss become overly preoccupied about the types of foods they eat. Although it is more beneficial for your long-term health to maintain a healthy balanced diet comprised of fruits, vegetables, nuts, lean meats/fish and complex carbohydrates, your body does not differentiate between these foods when comes to storing extra calories as fat. If you maintain a daily calorie surplus, that is, if you ingest more calories than you expend, you will gain weight regardless of the types of calories you ingest.

For example, lets say your total energy requirement (calculation above) is equal to 2000 calories per day and you've ingested 2012 calories per day. This means you've ingested 12 calories more than you've expended. Regardless of what types of foods these extra 12 calories consist of, whether it be a liquid or solid, fat or protein, fruit or chocolate bar, salad or french fries, your body will turn these extra calories into fat. Your body will then store this fat until it is needed for energy.

In theory, if you continue to maintain this calorie surplus daily, you would end up storing an additional 84 calories per week, 336 calories per month and 4368 calories per year (that's over 1 pound of fat). Keep in mind that this calculation is based on exceeding your daily energy expenditure by only 12 calories. That's equivalent to just over 1 cup of lettuce, 2 cups of plain black coffee, 1 M&M peanut or 1 glass of Kool-Aid. Since most people exceed their calorie expenditure by far more than 12 calories per day, it's no surprise that obesity is becoming the number one health problem in developed nations.

By calculating your total energy requirement (BMR + AMR) above, you will be able to roughly assess your daily calorie expenditure and calculate the amount of calories you require to maintain a daily calorie deficit. A daily calorie deficit, that is, expending more calories than you ingest, will allow you to lose weight regardless of the type of calories. Most experts agree that a 300-500 calorie daily deficit is safe and will allow for permanent weight loss provided a daily modest daily exercise program is followed.

If you find yourself ingesting more calories than your daily total energy requirement, you need to either reduce the amount of calories, increase the amount of daily physical activity, or preferably both. Both are preferential because increasing your BMR through daily physical activity will effectually allow you to burn more calories in the long-term. If you consistently decrease your calorie intake (through dieting) without increasing your physical activity levels, you risk reducing your BMR levels, forcing your body to burn less calories, which may eventually lead to further long-term weight gain and make it more difficult to lose the weight you've gained. Unfortunately, this is the scenario that most dieters face as they continue their desperate attempts to lose weight through dieting without physical activity. As we age, those who solely depend on dieting as a method of weight loss become even more frustrated since BMR levels naturally decline as we get older.

So how do you avoid falling into this vicious cycle? If your between 20 - 55 years of age, your AMR should consist of at least 120 - 200 minutes of moderate or heavy physical activity weekly. To prevent injuries and enhance recovery, the older you are, the more you will have to stay in the lower end of this range. If you're 55+, you should seek the guidance of an Exercise Specialist and your Physician for an appropriate guideline according to your health and fitness level.

Building muscle via strength conditioning is probably the easiest way to naturally increase your BMR. By incorporating weight training in your fitness regimen, your body will maintain or build more muscle which will burn more calories at rest, increasing your total daily energy expenditure. Cardiovascular exercise, eating small portions more frequently, supplementation, increasing protein intake, moving to a warmer climate, and adequate sleep are other ways to increase your BMR.

There are no quick fixes, pills or easy one-step diet solutions that will keep you fit and at a healthy weight. It's a lifestyle and requires programming, hard work and dedication. Inevitably, those who don't have time for such a lifestyle will soon have to make time for mental and physical illness. Prevention works and your health depends on it!

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