Basal metabolic rate (BMR) is the amount of energy expended while at rest in a neutrally temperate environment, in the post-absorptive state (meaning that the digestive system is inactive, which requires about twelve hours of fasting in humans). The release of energy in this state is sufficient only for the functioning of the vital organs, such as the heart, lungs, brain and the rest of the nervous system, liver, kidneys, sex organs, muscles and skin. BMR decreases with age and with the loss of lean body mass. Increased muscle mass can increase BMR. Aerobic fitness level, a product of cardiovascular exercise, while previously thought to have effect on basal or resting metabolic rate (RMR), has been shown in the 1990s not to correlate with RMR, when fat-free body mass was adjusted for (see following section "Aerobic vs. anaerobic exercise" for references). Illness, previously consumed food and beverages, environmental temperature, and stress levels can affect one's overall energy expenditure as well as one's BMR. [Note: BMR can be monitored (not measured) with BMT - See Presymtec.] Aerobic exercise is a type of exercise in which muscles draw on oxygen in the blood as well as fats and glucose, that increase cardiovascular endurance. ...

BMR is measured under very restrictive circumstances when a person is awake, but at complete rest. An accurate BMR measurement requires that the person's sympathetic nervous system not be stimulated. A more common and closely related measurement, used under less strict conditions, is resting metabolic rate (RMR).^[1] The Sympathetic Nervous System (SNS) is a branch of the autonomic nervous system. ...

BMR and RMR are measured by gas analysis through either direct or indirect calorimetry, though a rough estimation can be acquired through an equation using age, sex, height, and weight. Studies of energy metabolism using both methods provide convincing evidence for the validity of the respiratory quotient (R.Q.), which measures the inherent composition and utilization of carbohydrates, fats and proteins as they are converted to energy substrate units that can be used by the body as energy. The world’s first ice-calorimeter, used in the winter of 1782-83, by Antoine Lavoisier and Pierre-Simon Laplace, to determine the heat evolved in various chemical changes; calculations which were based on Joseph Black’s prior discovery of latent heat. ... The Respiratory Quotient is used in BMR calculations (basal metabolic rate) and is a form of indirect calorimetry. ... Lactose is a disaccharide found in milk. ... For other uses, see FAT. Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water. ... A representation of the 3D structure of myoglobin showing coloured alpha helices. ...

Nutrition and dietary considerations

Basal metabolic rate is usually by far the largest component of total caloric expenditure. However, the Harris-Benedict equations are only approximate and variation in BMR (reflecting varying body composition), in physical activity levels, and in energy expended in thermogenesis make it difficult to estimate the dietary consumption any particular individual needs in order to maintain body weight. 2000 kilocalories is often quoted but is no more than a guideline.

Physiology

Both basal metabolic rate and resting metabolic rate are usually expressed in terms of daily rates of energy expenditure. The early work of the scientists J. Arthur Harris and Francis G. Benedict showed that approximate values could be derived using body surface area (computed from height and weight), age, and sex, along with the oxygen and carbon dioxide measures taken from calorimetry. Studies also showed that by eliminating the sex differences that occur with the accumulation of adipose tissue by expressing metabolic rate per unit of "fat-free" or lean body weight, the values between sexes for basal metabolism are essentially the same^{[citation needed]}. Exercise physiology textbooks have tables to show the conversion of height and body surface area as they relate to weight and basal metabolic values. In physiology and medicine, the body surface area (BSA) is the measured or calculated surface of a human body. ... Adipose tissue is one of the main types of connective tissue. ... Exercise physiology is a term used by the sports industry to describe services involving the combination of exercise and physiology. ...

The primary organ responsible for regulating metabolism is the hypothalamus. The hypothalamus is located on the brain stem and forms the floor and part of the lateral walls of the third ventricle of the cerebrum. The chief functions of the hypothalamus are: The hypothalamus links the nervous system to the endocrine system via the pituitary gland (hypophysis). ... The brain stem is the lower part of the brain, adjoining and structurally continuous with the spinal cord. ... The telencephalon (IPA: ) is the name for the forebrain, a large region within the brain to which many functions are attributed. ...

1. control and integration of activities of the autonomic nervous system (ANS)
   • The ANS regulates contraction of smooth muscle and cardiac muscle, along with secretions of many endocrine organs such as the thyroid gland (associated with many metabolic disorders).
   • Through the ANS, the hypothalamus is the main regulator of visceral activities, such as heart rate, movement of food through the gastrointestinal tract, and contraction of the urinary bladder.
2. production and regulation of feelings of rage and aggression
3. regulation of body temperature
4. regulation of food intake, through two centers:
   • The feeding center or hunger center is responsible for the sensations that cause us to seek food. When sufficient food or substrates have been received and leptin is high, then the satiety center is stimulated and sends impulses that inhibit the feeding center. When insufficient food is present in the stomach and ghrelin levels are high, receptors in the hypothalamus initiate the sense of hunger.
   • The thirst center operates similarly when certain cells in the hypothalamus are stimulated by the rising osmotic pressure of the extracellular fluid. If thirst is satisfied, osmotic pressure decreases.

All of these functions taken together form a survival mechanism that causes us to sustain the body processes that BMR and RMR measure. This article or section is in need of attention from an expert on the subject. ... Cardiac muscle is a type of involuntary striated muscle found within the heart. ... RNA expression pattern Orthologs Human Mouse Entrez Ensembl Uniprot Refseq Location Pubmed search Leptin (from the Greek word leptos, meaning thin) is a 16 kDa protein hormone that plays a key role in regulating energy intake and energy expenditure, including the regulation (decrease) of appetite and (increase) of metabolism. ... Ghrelin is a hormone produced by P/D1 cells lining the acer of the human stomach that stimulate appetite. ... This article or section does not adequately cite its references or sources. ...

BMR estimation formulas

Several prediction equations exist. Historically most notable was Harris-Benedict equation, which was created in 1919.

The original equations from Harris and Benedict are:

• for men,
• for women,

where P is total heat production at complete rest, m is the weight, h is the stature (height), and a is the age, and with the difference in BMR for men and women being mainly due to differences in body weight. ^[2] For example, a 55 year old woman weighing 130 lb (59 kg) and 5 feet 6 inches (168 cm) tall would have a BMR of 1266 kcal per day or 52.8 kcal/h (61.3 watts).

It was the best prediction equation until recently, when MD Mifflin and ST St Jeor in 1990 created new equation:

• where s is +5 for males and −161 for female. According to this formula, the woman in the example above has a BMR of 1208 kcal per day.

During the last 100 years, lifestyles have changed and a survey in 2005 showed it to be about 5% more accurate.

To calculate daily calorie needs, this BMR value is multiplied by a factor with a value between 1.2 and 1.9, depending on the person's activity level.

An online BMR calculator for both metric and non-metric values can be found at http://www.bmi-calculator.net/bmr-calculator/.

Animal BMR

Kleiber's law relates the BMR for animals of different sizes and the observations indicate that the BMR is proportional to the 3/4 power of body mass. Warm blooded, cold blooded and unicellular animals fit on different curves. Kleibers law, named after Max Kleibers biological work in the early 1930s, is the observation that, for the vast majority of animals, an animals metabolic rate scales to the 3/4 power of the animals mass. ... Warm-blooded animals maintain thermal homeostasis; which is keeping your body temperature at a constant level. ... For the 1995 movie about hitmen, see Coldblooded (movie). ... A microorganism or microbe is an organism that is so small that it is microscopic (invisible to the naked eye). ...

Biochemistry

This section does not cite any references or sources. (April 2008) Please help improve this section by adding citations to reliable sources. Unverifiable material may be challenged and removed.

About 70% of a human's total energy expenditure is due to the basal life processes within the organs of the body (see table). About 20% of one's energy expenditure comes from physical activity and another 10% from thermogenesis, or digestion of food.^{[citation needed]} All of these processes require an intake of oxygen along with coenzymes to provide energy for survival (usually from macronutrients like carbohydrates, fats, and proteins) and expel carbon dioxide, which is explained by the Krebs cycle. The liver is the largest internal organ in the human body, and is an organ present in vertebrates and some other animals. ... For other uses, see Brain (disambiguation). ... The heart and lungs, from an older edition of Grays Anatomy. ... Kidneys viewed from behind with spine removed The kidneys are bean-shaped excretory organs in vertebrates. ... A top-down view of skeletal muscle Skeletal muscle is a type of striated muscle, usually attached to the skeleton. ... Thermogenesis is the process of heat production in organisms. ... The citric acid cycle (also known as the tricarboxylic acid cycle, the TCA cycle, or the Krebs cycle) is a series of chemical reactions of central importance in all living cells that utilize oxygen as part of cellular respiration. ...

What enables the Krebs cycle to perform metabolic changes to fats, carbohydrates, and proteins is energy which can be defined as the ability or capacity to do work. The breakdown of large molecules into smaller molecules associated with release of energy is catabolism. The building up process is termed anabolism. The breakdown of proteins into amino acids is an example of catabolism while the formation of proteins from amino acids is an anabolic process.

Exergonic reactions are energy-releasing reactions and are generally catabolic. Endergonic reactions require energy and include anabolic reactions and the contraction of muscle. Metabolism is the total of all catabolic, exergonic, anabolic, endergonic reactions. An exergonic reaction is a chemical reaction where the variation of free energy is negative. ...

Adenosine Triphosphate (ATP) is the intermediate molecule that drives the exergonic transfer of energy to switch to endergonic anabolic reactions used in muscle contraction. This is what causes muscles to work which can require a breakdown, and also to build in the rest period, which occurs during the strengthening phase associated with muscular contraction. ATP is composed of adenine, a nitrogen containing base, ribose, a five carbon sugar (collectively called adenosine), and three phosphate groups. ATP is a high energy molecule because it stores large amounts of energy in the chemical bonds of the two terminal phosphate groups. The breaking of these chemical bonds in the Krebs Cycle provides the energy needed for muscular contraction.

Glucose

Because the ratio of hydrogen to oxygen atoms in all carbohydrates is always the same as that in water — that is, 2 to 1 — all of the oxygen consumed by the cells is used to oxidize the carbon in the carbohydrate molecule to form carbon dioxide. Consequently, during the complete oxidation of a glucose molecule, six molecules of carbon dioxide are produced and six molecules of oxygen are consumed. The most fundamental reactions in chemistry are the redox processes. ...

The overall equation for this reaction is:

C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O

Because the gas exchange in this reaction is equal, the respiratory quotient for carbohydrate is unity or 1.0:

R.Q. = 6 CO₂ / 6 O₂

Fats

The chemical composition for fats differs from that of carbohydrates in that fats contain considerably fewer oxygen atoms in proportion to atoms of carbon and hydrogen. When listed on nutritional information tables, fats are generally divided into six categories: total fats, saturated fatty acid, polyunsaturated fatty acid, monounsaturated fatty acid, dietary cholesterol, and trans fatty acid. From a basal metabolic or resting metabolic perspective, more energy is needed to burn a saturated fatty acid than an unsaturated fatty acid. The fatty acid molecule is broken down and categorized based on the number of carbon atoms in its molecular structure. The chemical equation for metabolism of the twelve to sixteen carbon atoms in a saturated fatty acid molecule shows the difference between metabolism of carbohydrates and fatty acids. Palmitic acid is a commonly studied example of the saturated fatty acid molecule. When palmitic acid is broken down, more oxygen is needed and more carbon dioxide is produced, but the respiratory quotient moves below unity to account for the increased energy required to burn fat molecules--generally 9 kilocalories per gram of fat versus 4 kilocalories for a gram of carbohydrate or protein.
↑NOTE: Please fact check the last phrase; I believe this to be the energy released to the organism by catabolism of fats (beta oxidation), not the energy input required by the organism to catabolyze them. Two completely different things. In chemistry, especially biochemistry, a fatty acid is a carboxylic acid (or organic acid), often with a long aliphatic tail (long chains), either saturated or unsaturated. ... A polyunsaturated fatty acid (PUFA) is a class of unsaturated fat that contains more than one double bond. ... An unsaturated fat is a fat or fatty acid in which there are one or more double bonds in the fatty acid chain. ... Cholesterol is a sterol (a combination steroid and alcohol). ... A trans fatty acid (commonly shortened to trans fat) is an unsaturated fatty acid molecule that contains a trans double bond between carbon atoms, which makes the molecule less kinked compared to cis fat. Research suggests a correlation between diets high in trans fats and diseases like atherosclerosis and coronary... Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is one of the most common saturated fatty acids found in animals and plants. ...

The overall equation for the substrate utilization of palmitic acid is:

C₁₆H₃₂O₂ + 23 O₂ → 16 CO₂ + 16 H₂O

Thus the R.Q. for palmitic acid is 0.696:

R.Q. = 16 CO₂ / 23 O₂ = 0.696

Proteins

Proteins are composed of carbon, hydrogen, oxygen, and nitrogen arranged in a variety of ways to form a large combination of amino acids. Unlike fat the body has no storage deposits of protein. All of it is contained in the body as important parts of tissues, blood hormones, and enzymes. The structural components of the body that contain these amino acids are continually undergoing a process of breakdown and replacement. The respiratory quotient for protein metabolism can be demonstrated by the chemical equation for oxidation of albumin: In chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. ...

C₇₂H₁₁₂N₂O₂₂S + 77 O₂ → 63 CO₂ + 38 H₂O + SO₃ + 9 CO(NH₂)₂

The R.Q. for albumin is 63 CO₂/ 77 O₂ = 0.818

The reason why this is important in the process of understanding protein metabolism is because the body can blend the three macronutrients and based on the mitochondrial density, a preferred ratio can be established which determines how much fuel is utilized in which packets for work accomplished by the muscles. Protein catabolism (breakdown) has been estimated to supply 10% to 15% of the total energy requirement during a two hour training session. However, if a person's muscle glycogen supplies are low from previous exercise sessions, the amount of energy derived from protein catabolism could increase from 15% to 45%. This process could severely degrade the protein structures needed to maintain survival such as contractile properties of proteins in the heart, cellular mitochondria, myoglobin storage, and metabolic enzymes within muscles.

The oxidative system (aerobic) is the primary source of ATP supplied to the body at rest and during low intensity activities and uses primarily carbohydrates and fats as substrates. Protein is not normally metabolized significantly, except during long term starvation and long bouts of exercise (greater than 90 minutes.) At rest approximately 70% of the ATP produced is derived from fats and 30% from carbohydrates. Following the onset of activity, as the intensity of the exercise increases, there is a shift in substrate preference from fats to carbohydrates. During high intensity aerobic exercise, almost 100% of the energy is derived from carbohydrates, if an adequate supply is available.

Exercise physiology

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There are several companies testing the public for the respiratory quotient that identifies heart rates attributed to substrate utilization to assist with weight loss. It is theorized that if a person can more accurately know what amount of energy from carbohydrates, fats and proteins is needed to survive, then a person can select consumption patterns to more efficiently match what is required by the body for daily activities. Thus the emphasis shifts from caloric restriction, which slows the BMR or RMR and causes frustration of weight management goals, to substrate utilization, which focuses on what the body needs to stay healthy. By measuring the carbon dioxide expended (VCO₂) in ml/min and dividing that by oxygen consumed (VO₂) in ml/min you can determine the R.Q., which can then be compared to heart rate for purposes of application. The Balke VO₂ Max running test could help to estimate what cardiac output level could be achieved by a 15 minute level of exertion using the following equation: (((Total distance covered ÷ 15) - 133) × 0.172) + 33.3. For a 50 year old male, weighing 150 pounds (68 kg), standing 69¾ inches (177 cm), that would be 47 ml/kg/min if he ran 3200 meters in 15 min. However, the same test using gas analysis would reveal more accurate information such as a peak VO₂ of 51.8 ml/kg/min at an anaerobic threshold of 126 beats per minute, at 30.2 ml/kg/min and 58% of VO₂ max. This would be 1725 meters in 15 minutes according to the Balke formula. But only gas analysis could determine the value accurately for purposes of losing weight successfully if that was an objective. So if a person had a measured BMR or RMR of 1610 kcal by gas analysis, and they walked around a track for 10 minutes with a heart rate at 94 beats per minute, they would consume all 25 grams of fat in a single quarter pounder with cheese with a previously determined anaerobic threshold of 126 beats per minute from a Peak VO₂ of 51.8 ml/kg/minute. This analysis is precisely what is lacking from the current regime of dieting programs that stress caloric restriction, total calorie management from scale measure, and RMR or BMR from formulas using height, weight, age, activity level. These methods fail to appreciate the Krebs cycle and the ability of the body to adapt to lifestyle choices through BMR and RMR adjustment. By measuring the body with gas analysis as the principal determinant of BMR under strict fasting conditions, or RMR using less stringent measures, a person who wants to achieve a more optimal level of conditioning is more accurately directed to energy utilization patterns that are effective. VO2 max is the maximum capacity to transport and utilize oxygen during incremental exercise. ...

The reason why it's important to understand this difference with exercise testing is because it's essential to take into consideration whether or not the heart is capable of providing exercise stressed muscles with enough oxygen. Conditions such as obesity will affect the ability of formulas to accurately predict external work because the need to move a larger body changes the oxygen cost during exercise at least 5.8 ml/min for each kg of body weight.

Aerobic vs. anaerobic exercise

Studies published in 1992^[3] and 1997^[4] indicate that the level of aerobic fitness of an individual does not have any correlation with the level of resting metabolism. Both studies find that aerobic fitness levels do not improve the predictive power of Fat Free Mass for resting metabolic rate.

This suggests that anaerobic exercise may be more effective in raising the resting metabolic rate (Basal Metabolic Rate). Anaerobic exercise, such as weight lifting, builds additional muscle mass, which is Fat Free Mass. Additional Fat Free Mass will lead to a higher resting metabolic rate according to the above studies. Also, while aerobic exercise is beneficial for cardiovascular reasons as well as direct calorie burning, the above studies indicate it is not useful for increasing resting metabolism. Fox and Haskell formula Anaerobic exercise is used by athletes in non-endurance sports to build power and by body builders to build muscle mass. ... Weightlifting is a sport where competitors attempt to lift heavy weights mounted on steel bars. ... Aerobic exercise refers to exercise that involves or improves oxygen consumption by the body. ...

Longevity

In 1926 Raymond Pearl proposed that longevity varies inversely with basal metabolic rate (the "rate of living hypothesis"). Support for this hypothesis comes from the fact that mammals with larger body size have longer maximum life spans and the fact that the longevity of fruit flies varies inversely with ambient temperature.^[5] Additionally, the life span of houseflies can be extended by preventing physical activity.^[6] Raymond Pearl (3 June 1879 - 17 November 1940) was an American biologist, who spent most of his career at Johns Hopkins University in Baltimore. ... Longevity is a term that generally refers to long life or great duration of life.[1] Reflections on longevity have usually gone beyond acknowledging the basic shortness of human life and have included thinking about methods to extend life. ... Maximum life span is a measure of the maximum number of years a member of a group has been observed to survive. ... Binomial name Meigen, 1830[1] Drosophila melanogaster (from the Greek for black-bellied dew-lover) is a two-winged insect that belongs to the Diptera, the order of the flies. ... For other uses, see Temperature (disambiguation). ...

But the ratio of resting metabolic rate to total daily energy expenditure can vary between 1.6 to 8.0 between species of mammals. Animals also vary in the degree of coupling between oxidative phosphorylation and ATP production, the amount of saturated fat in mitochondrial membranes, the amount of DNA repair, and many other factors that affect maximum life span.^[7] Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... Chemiosmosis is the diffusion of ions across a membrane. ... Saturated fat is fat that consists of triglycerides containing only saturated fatty acids. ... Mitochondria structure : 1) Inner membrane 2) Outer membrane 3) Crista 4) Matrix The outer membrane refers to the outside membranes of Gram-negative bacteria, the chloroplast, or the mitochondria. ... DNA damage resulting in multiple broken chromosomes DNA repair refers to a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. ...

Organism Longevity and Basal Metabolic Rate

In allometric scaling maximum potential life span (MPLS) is directly related to metabolic rate (MR), where MR is the recharge rate of a biomass made up of covalent bonds subject to deterioration over time from thermodynamic, entropic pressure. Metabolism is essentially about redox coupling, and has nothing to do with thermogenesis. Metabolic efficiency (ME) is then expressed as the efficiency of this coupling, a ratio of amperes captured and used by biomass (W), to the amperes available for that purpose. MR is measured in watts, W is measured in grams. These factors are combined in a power law, an elaboration on Kleiber's Law relating MR to W and MPLS, that appears as MR = W^ (4ME-1)/4ME. When ME is 100%, MR = W^3/4, what is known popularly as quarter power scaling, a version of allometric scaling premised upon unreal estimations of biological efficiency.

The equation reveals that as ME drops below 20%, for W < one gram, MR/MPLS increases so dramatically as to endow W with virtual immortality by 16%. The smaller W is to begin with, the more dramatic is the increase in MR as ME diminishes. All of the cells of an organism fit into this range, i.e., less than one gram, and so this MR will be referred to as BMR.

But the equation reveals that as ME increases over 25%, BMR approaches zero. The equation also shows that for all W > one gram, where W is the organization of all of the BMRs of the organism's structure, but also includes the activity of the structure, as ME increases over 25%, MR/MPLS increases rather than decreases, as it does for BMR. An MR made up of an organization of BMRs will be referred to as an FMR. As ME decreases below 25%, FMR diminishes rather than increases as it does for BMR.

The antagonism between FMR and BMR is what marks the process of aging of biomass W in energetic terms. The ME for the organism is the same as that for the cells, such that the success of the organism's ability to find food (and lower its ME), is key to maintaining the BMR of the cells driven, otherwise, by starvation, to approaching zero; while at the same time a lower ME diminishes the FMR/MPLS of the organism.

Medical considerations

Each person's metabolism is unique due to their unique physical makeup and physical behavior. For some, this makes weight management a very difficult undertaking requiring sophisticated expertise. There are a number of medical adjustments to natural human processes that can affect one's metabolism.

Menopause affects metabolism but in different ways for different people, thus hormones are sometimes used to minimize the effects of menopause. Weight training can have a longer impact on metabolism than aerobic training, but there are no formulas currently written which can predict the length and duration of a raised metabolism from trophic changes with anabolic neuromuscular training. Gastric bypass surgery is used to reduce the content capacity of the stomach, bringing caloric intake down and lowering thermogenesis. Because the surgery significantly reduces caloric consumption, it will decrease BMR and RMR over time in the same fashion as aging, because the volume of the stomach is reduced. The stomach along with the rest of the digestive tract is a major contributor to BMR and RMR. Celiac disease, which reduces the ability of the stomach to digest food, may also reduce BMR and RMR. Celiac disease is fairly common, occurring in 1% of the U.S. population, with 2 million undiagnosed.^{[8][citation needed]} The word menopause literally means the permanent physiological, or natural, cessation of menstrual cycles, from the Greek roots meno (month) and pausis (a pause, a cessation). ... This article is about strength training using weight (gravity) to generate resistance to contraction. ... Aerobic exercise refers to exercise that involves or improves oxygen consumption by the body. ... Gastric bypass procedures (GBP) are any of a group of similar operations used to treat morbid obesity—the severe accumulation of excess weight as fatty tissue—and the health problems (comorbidities) it causes. ... Coeliac disease (also termed non-tropical sprue, celiac disease and gluten intolerance) is an autoimmune disease characterised by chronic inflammation of the proximal portion of the small intestine caused by exposure to certain dietary gluten proteins. ... Coeliac disease (pronounced ), also spelt celiac disease, is an autoimmune disorder of the small bowel that occurs in genetically predisposed people of all ages from middle infancy. ...

Cardiovascular implications

Heart rate is determined by the medulla oblongata and part of the pons, two organs located inferior to the hypothalamus on the brain stem. Heart rate is important for basal metabolic rate and resting metabolic rate because it drives the blood supply, stimulating the Krebs cycle. During exercise that achieves the anaerobic threshold, it is possible to deliver substrates that are desired for optimal energy utilization. The anaerobic threshold is defined as the energy utilization level of heart rate exertion that occurs without oxygen during a standardized test with a specific protocol for accuracy of measurement, such as the Bruce Treadmill protocol (see Metabolic equivalent). With four to six weeks of targeted training the body systems can adapt to a higher perfusion of mitochondrial density for increased oxygen availability for the Krebs cycle, or tricarboxylic cycle, or the glycolitic cycle. This in turn leads to a lower resting heart rate, lower blood pressure, and increased resting or basal metabolic rate. The medulla oblongata is the lower portion of the brainstem. ... For other uses, see Pons (disambiguation). ... A unit of metabolic equivalent, or MET, is defined as the number of calories consumed by an organism per minute in an activity relative to the Basal metabolic rate (BMR/RMR, see below). ...

Knowing what the body burns at rest or through exercise yields (via heart rate monitoring) a targeted program of energy utilization based on metabolic performance. The resting heart rate is correlated to the resting metabolic rate because of the singular contribution made by the heart to survival. By measuring heart rate we can then derive estimations of what level of substrate utilization is actually causing biochemical metabolism in our bodies at rest or in activity. This in turn can help a person to maintain an appropriate level of consumption and utilization by studying a graphical representation of the anaerobic threshold. This can be confirmed by blood tests and gas analysis using either direct or indirect calorimetry to show the effect of substrate utilization. The measures of basal metabolic rate and resting metabolic rate are becoming essential tools for maintaining a healthy body weight.

References

1. ^ CaloriesPerHour.com. Diet and Weight Loss Tutorial. Calculating BMR and RMR. Retrieved on 2008-01-26.
2. ^ Harris J, Benedict F (1918). "A Biometric Study of Human Basal Metabolism.". Proc Sci U S A 4 (12): 370-3. PMID 16576330. 
3. ^ CE Broeder, KA Burrhus, LS Svanevik and JH Wilmore (1992). American Journal of Clinical Nutrition. The effects of aerobic fitness on resting metabolic rate. Retrieved on 2007-11-23.
4. ^ D. A. Smith, J. Dollman, R. T. Withers, M. Brinkman, J. P. Keeves, and D. G. Clark(1997). Journal of Applied Physiology. Relationship between maximum aerobic power and resting metabolic rate in young adult women. Retrieved on 2007-11-23.
5. ^ Miquel J, Lundgren PR, Bensch KG, Atlan H (1976). "The effects of temperature on the aging process have been investigated in approximately 3500 imagoes of male Drosophila melanogaster". MECHANISMS OF AGING AND DEVELOPMENT 5 (5): 347-370. PMID 823384. 
6. ^ Ragland SS, Sohal RS (1975). "Ambient temperature, physical activity and aging in the housefly, Musca domestica". EXPERIMENTAL GERONTOLOGY 10 (5): 279-289. doi:10.1016/0531-5565(75)90005-4. PMID 1204688. 
7. ^ Speakman JR, Selman C, McLaren JS, Harper EJ (2002). "Living fast, dying when? The link between aging and energetics". THE JOURNAL OF NUTRITION 132 (6, Supplement 2): 1583S-1597S. PMID 12042467. 
8. ^ MedlinePlus: Celiac Disease. Retrieved on 2006-09-15.

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2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... is the 26th day of the year in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 327th day of the year (328th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 327th day of the year (328th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 258th day of the year (259th in leap years) in the Gregorian calendar. ...

See also

• Thermic effect of food

Thermic effect of food (also commonly known simply as thermic effect when the context is known), or TEF in shorthand, is the increment in energy expenditure above resting metabolic rate due to the cost of processing food for storage and use. ...

External links

• The original 1918 Harris-Benedict article (free full text)
• Harris-Benedict study. Detailed discusion of antecedents, data, measurements, statistics (Published by The Carnegie Institution of Washington 1919)
• What do BMR and RMR stand for?
• Dietary Guidelines from the U.S. Government
• Food Consumption patterns in the U.S.
• [1] Body composition Explained
• [2]Harvard University's explanation of Metabolic Equivalent Tables
• [3] Temporal Trend Shifts and the Ecological Perspectives on Weight Gain in the US
• [4] Information on the National Weight Control Registry.
• [5] Health Trends in the United States
• [6] BMR as affected by alcohol and nicotine