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| | This particular next step to such [http://Search.huffingtonpost.com/search?q=game%27%27s+success&s_it=header_form_v1 game''s success] is that can it produces the picture that it''s a multi-player game. I think it''s a fantasy due to the you don''t do all that is necessary directly with any other player. You don''t fight and explore in unison like you would in Wow, of play to prevent another player even as a result of with a turn-by-turn purpose comparable to Chess. Any time you raid another player''s village, by which player is offline combined with you could at this particular same time just be particularly raiding a random computer-generated village.<br><br>Go online for help. Practically every game has its possess legion of devoted devotees, lots of which waste countless hours crafting intensive maps and guides. Additionally there are newsgroups where you are qualified to speak one on with other players. Benefit from this goldmine and it is easy to eventually get past that level of cla you have been attached on forever.<br><br>Throne Rush has an equivalent for just about my way through Clash. Instead about a Town Hall, it features Castle. If you enjoyed this article and you would such as to receive more details regarding [http://circuspartypanama.com hack clash of clans ifile] kindly check out our web-page. Instead of Clans, it has Brotherhoods. Instead of Trophies, it has Morale. Perhaps the one point it takes to the next step is its Immortal Personas. clash of clans has a Barbarian King and a substantial Archer Queen which are special units that can be reused in battle inch they just [http://require.org/ require] times of time to heal back to full nicely. Throne Rush has similar heroes that could be hired, but they will extreme and more packed. They play almost the same way, but i think players will indulge in using four or seven Immortal Heroes instead related to just two, as long as they dont fool the balance of video game too severely.<br><br>Deviate of Clans is fully a popular sport designed to end up being dabbled in on multiple systems, the car . iOS and also google's android. The overall game is incredibly intriguing but presently many comes a spot on legend, where the music player gets trapped because pointing to not enough gems. However, this problem is now able to easily turn into resolved.<br><br>Make sure you may not let online games take over your occurrence. Game titles can be quite additive, therefore you have to make assured you moderate the period of time that you investing activity such games. In case you invest an excessive level of time playing video game, your actual life could actually begin to falter.<br><br>Precious metal and Elixir would function as main sources available inside of Clash of Clans. Each of these both are necessary and can be gathered by a associated with ways. Frontrunners of people can use structures, recover the cash some other tribes or even clash of clans hack tools for acquiring both of them.<br><br>Now that you have read this composition, you need to have an easier time locating and loving video games in your lifetime. Notwithstanding your favored platform, from your cellphone to any own computer, playing and enjoying video gaming enable you to take the benefit of the worries of the actual busy week get details. |
| '''Basal metabolic rate''' ('''BMR'''), and the closely related '''resting metabolic rate''' ('''RMR'''), is the amount of [[food energy|energy]] expended daily by humans and other animals at rest. Rest is defined as existing in a neutrally [[temperate]] environment while in the post-[[absorptive state]]. In plants, different considerations apply.
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| The release, and using, of energy in this state is sufficient only for the functioning of the vital organs, the [[heart]], [[lungs]], [[nervous system]], [[kidneys]], [[liver]], [[intestine]], [[sex organs]], [[muscles]], and [[skin]].
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| ==Description==
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| The body's generation of heat is known as [[thermogenesis]] and it can be measured to determine the amount of energy expended.
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| BMR generally decreases with age and with the decrease in [[lean body mass]] (as may happen with aging). Increasing muscle mass increases BMR, although the effect is not significant enough to act as a weight-loss method. [[Aerobic respiration|Aerobic]] fitness level, a product of [[cardiovascular exercise]], while previously thought to have effect on BMR, has been shown in the 1990s not to correlate with BMR when adjusted for fat-free body mass.{{Citation needed|date=June 2011}} New research{{Citation needed|date=April 2009}} has, however, come to light that suggests anaerobic exercise does increase resting energy consumption (see "[[Basal metabolic rate#Aerobic vs. anaerobic exercise|Aerobic vs. anaerobic exercise]]"). Illness, previously consumed food and beverages, environmental temperature, and stress levels can affect one's overall energy expenditure as well as one's BMR.
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| [[File:Indirect calorimetry laboratory with canopy hood.jpg|thumb|Indirect calorimetry laboratory with canopy hood (dilution technique)]]
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| BMR is measured under very restrictive circumstances when a person is awake. An accurate BMR measurement requires that the person's [[sympathetic nervous system]] not be stimulated, a condition which requires complete rest. A more common and closely related measurement, used under less strict conditions, is resting metabolic rate (RMR).<ref>{{cite web
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| |author=CaloriesPerHour.com
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| |title=Diet and Weight Loss Tutorial
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| |work=Calculating BMR and RMR
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| |url=http://www.caloriesperhour.com/tutorial_BMR.php
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| |accessdate=2008-01-26| archiveurl= http://web.archive.org/web/20080105084119/http://www.caloriesperhour.com/tutorial_BMR.php| archivedate= 5 January 2008 <!--DASHBot-->| deadurl= no}}</ref>
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| 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 [[carbohydrate]]s, [[fat]]s and [[protein]]s as they are converted to energy substrate units that can be used by the body as energy.
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| ==Nutrition and dietary considerations==
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| Basal metabolism is usually by far the largest component of total caloric expenditure. However, the [[Harris–Benedict equation]]s 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.
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| ==Physiology==
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| 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 mass]], the values between sexes for basal metabolism are essentially the same. [[Exercise physiology]] textbooks have tables to show the conversion of height and body surface area as they relate to weight and basal metabolic values.
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| The primary [[Organ (anatomy)|organ]] responsible for regulating metabolism is the [[hypothalamus]]. The hypothalamus is located on the [[diencephalon]] and forms the floor and part of the lateral walls of the third ventricle of the [[cerebrum]]. The chief functions of the hypothalamus are:
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| :#control and integration of activities of the [[autonomic nervous system]] (ANS)
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| :#*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).
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| :#*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.
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| :#production and regulation of feelings of rage and aggression
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| :#regulation of body temperature
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| :#regulation of food intake, through two centers:
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| :#*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.
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| :#*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.
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| All of these functions taken together form a survival mechanism that causes us to sustain the body processes that BMR and RMR measure.
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| ===BMR estimation formulas===
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| Several prediction equations exist. Historically, the most notable one was the [[Harris-Benedict equation]], which was created in 1919.
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| '''The Original Harris-Benedict Equation:''' | |
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| :*for men, <math>P = \left ( \frac {13.7516 m} {1 ~ \mbox {kg}} + \frac {5.0033 h} {1 ~ \mbox {cm}} - \frac {6.7550 a} {1 ~ \mbox {year}} + 66.4730 \right ) \frac {\mbox {kcal}} {\mbox {day}}</math>
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| :*for women, <math>P = \left ( \frac {9.5634 m} {1 ~ \mbox {kg}} + \frac {1.8496 h} {1 ~ \mbox {cm}} - \frac {4.6756 a} {1 ~ \mbox {year}} + 655.0955 \right ) \frac {\mbox {kcal}} {\mbox {day}}</math>
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| where ''P'' is total heat production at complete rest, ''m'' is the weight, ''h'' is the height, and ''a'' is the age, and with the difference in BMR for men and women being mainly due to differences in body weight.<ref name="Harris1918">{{cite journal
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| | author = Harris J, Benedict F
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| | title = A Biometric Study of Human Basal Metabolism
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| | journal =PNAS
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| | volume = 4
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| | issue = 12
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| | pages = 370–3
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| | year = 1918
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| | pmid = 16576330
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| | doi = 10.1073/pnas.4.12.370
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| | pmc = 1091498
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| | bibcode=1918PNAS....4..370H
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| }}</ref> 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 1272 kcal per day or 53 kcal/h (61.3 watts).
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| In 1984, the original Harris-Benedict equations were revised<ref>{{cite journal
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| |pages=168–182 |title=The Harris Benedict equation reevaluated: resting energy requirements and the body cell mass |year=1984 |last1=Roza |first1=Allan M |last2=Shizgal |first2=Harry M |journal=The American Journal of Clinical Nutrition |volume=40}}</ref> using new data. In comparisons with actual expenditure, the revised equations were found to be more accurate.<ref>{{cite journal |pages=1955–63 |title=Calculating the basal metabolic rate and severe and morbid obesity |year=2001 |last1=Müller |first1=B |last2=Merk |first2=S |last3=Bürgi |first3=U |last4=Diem |first4=P |journal=Praxis (Bern 1994) |volume=90 |issue=45}}</ref>
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| '''The Revised Harris-Benedict Equation:'''
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| :*for men, <math>P = \left ( \frac {13.397 m} {1 ~ \mbox {kg}} + \frac {4.799 h} {1 ~ \mbox {cm}} - \frac {5.677 a} {1 ~ \mbox {year}} + 88.362 \right ) \frac {\mbox {kcal}} {\mbox {day}}</math>
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| :*for women, <math>P = \left ( \frac {9.247 m} {1 ~ \mbox {kg}} + \frac {3.098 h} {1 ~ \mbox {cm}} - \frac {4.330 a} {1 ~ \mbox {year}} + 447.593 \right ) \frac {\mbox {kcal}} {\mbox {day}}</math>
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| It was the best prediction equation until 1990, when Mifflin ''et al.''<ref>{{cite journal |pmid=2305711 |year=1990 |last1=Mifflin |first1=MD |last2=St Jeor |first2=ST |last3=Hill |first3=LA |last4=Scott |first4=BJ |last5=Daugherty |first5=SA |last6=Koh |first6=YO |title=A new predictive equation for resting energy expenditure in healthy individuals |volume=51 |issue=2 |pages=241–7 |journal=The American journal of clinical nutrition}}</ref> introduced the equation:
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| '''The Mifflin St Jeor Equation:'''
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| :*<math>P = \left ( \frac {10.0 m} {1 ~ \mbox {kg}} + \frac {6.25 h} {1 ~ \mbox {cm}} - \frac {5.0 a} {1 ~ \mbox {year}} + s \right ) \frac {\mbox {kcal}} {\mbox {day}}</math>, where ''s'' is +5 for males and −161 for females.
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| According to this formula, the woman in the example above has a BMR of 1204 kcal per day.
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| During the last 100 years, lifestyles have changed and Frankenfield ''et al.''<ref>{{cite journal |pages=775–89 |doi=10.1016/j.jada.2005.02.005 |title=Comparison of Predictive Equations for Resting Metabolic Rate in Healthy Nonobese and Obese Adults: A Systematic Review |year=2005 |last1=Frankenfield |first1=David |last2=Roth-Yousey |first2=Lori |last3=Compher |first3=Charlene |journal=Journal of the American Dietetic Association |volume=105 |issue=5 |pmid=15883556}}</ref> showed it to be about 5% more accurate.
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| These formulas are based on body weight, which does not take into account the difference in metabolic activity between [[lean body mass]] and body fat. Other formulas exist which take into account lean body mass, two of which are the Katch-McArdle formula, and Cunningham formula. However, the Cunningham formula is used to predict RMR instead of BMR.<ref>{{cite book|last=Dunford|first=M|title=Nutrition for Sport and Exercise|year=2007|publisher=Brooks/Cole|isbn=9780495014836|pages=57|url=http://books.google.com.au/books?id=arqNy5e1t60C}}</ref>
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| '''The Katch-McArdle Formula (BMR):'''
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| :*<math> P = 370 + \left( {21.6 \cdot LBM} \right)</math>, where ''LBM'' is the lean body mass in kg.<ref name="BFFM">{{cite book |first=Tom |last=Venuto |title=Burn the Fat, Feed the Muscle |year=2003 |isbn=0-9724132-0-0}}{{Page needed|date=March 2012}}</ref>
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| According to this formula, if the woman in the example has a [[body fat percentage]] of 30%, her BMR would be 1263 kcal per day.
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| '''The Cunningham Formula (RMR):'''
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| :*<math> P = 500 + \left( {22 \cdot LBM} \right)</math>, where ''LBM'' is the lean body mass in kg
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| Since lean body mass is metabolically active vs. fat cells which need very few calories to be sustained, these formula tend to be more accurate, especially with athletes who have above average lean mass and little body fat.
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| To calculate daily calorie needs, the BMR value is multiplied by a factor with a value between 1.2 and 1.9, depending on the person's [[physical activity level]].
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| ===Causes of individual differences in BMR===
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| The basal metabolic rate varies between individuals. One study of 150 adults representative of the population in Scotland reported basal metabolic rates from as low as 1027 kcal per day (4301 kJ/day) to as high as 2499 kcal/day (10455 kJ/day); with a mean BMR of 1500 kcal/day (6279 kJ/day). Statistically, the researchers calculated that 62.3% of this variation was explained by differences in [[fat free mass]]. Other factors explaining the variation included [[fat mass]] (6.7%), age (1.7%), and [[experimental error]] including within-subject difference (2%). The rest of the variation (26.7%) was unexplained. This remaining difference was not explained by sex nor by differing tissue size of highly energetic organs such as the brain.<ref name="Johnstone">{{cite journal |pmid=2305711 |year=2005 |last1=Johnstone |first1=Alexandra M |last2=Murison |first2=Sandra D |last3=Duncan |first3=Jackie S |last4=Rance |first4=Kellie A |last5=Speakman |first5=John R |title=Factors influencing variation in basal metabolic rate include fat-free mass, fat mass, age, and circulating thyroxine but not sex, circulating leptin, or triiodothyronine |volume=82 |issue=5 |pages=941–948 |journal=American Journal of Clinical Nutrition |last6=Koh |first6=YO}}</ref>
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| Thus there are differences in BMR even when comparing two subjects with ''the same'' [[lean body mass]]. The top 5% of people are metabolizing energy 28-32% faster than individuals with the lowest 5% BMR.<ref name="Speakman">{{cite journal |pmid=15674765|year=2004 |last1=Speakman |first1=John R. |last2=Król |first2=Elzbieta |last3=Johnson |first3=Maria S. |title=The Functional Significance of Individual Variation in Basal Metabolic Rate |volume=77 |issue=6 |pages=900–915 |journal=Physiological and Biochemical Zoology |doi=10.1086/427059}}</ref> For instance, one study reported an extreme case where two individuals with the same lean body mass of 43 kg had BMRs of 1075 kcal/day (4.5 MJ/day) and 1790 kcal/day (7.5 MJ/day). This difference of 715 kcal/day (67%) is equivalent to one of the individuals completing a 10 kilometer run every day.<ref name="Speakman" />
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| ===Animal BMR===
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| [[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]], [[Ectotherm|cold blooded]] and [[unicellular]] organisms fit on different curves.
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| ==Biochemistry==
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| {| style="float:right;" class="wikitable"
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| |-
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| ! colspan="2" | Energy expenditure breakdown
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| |-
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| | [[Liver]]
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| |27%
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| |-
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| | [[Brain]]
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| | 19%
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| |-
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| | Other [[Organs]]
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| | 19%
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| |-
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| | [[Skeletal Muscle]]
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| | 18%
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| |-
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| | [[Kidneys]]
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| | 10%
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| |-
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| | [[Heart]]
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| | 7%
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| |}
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| [[File:Postprandial thermogenesis.png|thumb|''Postprandial thermogenesis'' increases in basal metabolic rate occur at different degrees depending on consumed food composition.]]
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| 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 (''postprandial thermogenesis'').<ref>{{Cite book |title=Exercise Physiology |edition=2nd |first=William D. |last=McArdle |year=1986 |publisher=Lea & Febigier |location=Philadelphia}}{{Page needed|date=January 2012}}</ref> 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, due to processing by the [[Krebs cycle]].
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| For the BMR, most of the energy is consumed in maintaining fluid levels in tissues through osmoregulation, and only about one-tenth is consumed for [[work (physics)|mechanical work]], such as digestion, heartbeat, and breathing.<ref>{{cite book|author=Lisa Gordon-Davis|title=Hospitality Industry Handbook on Nutrition and Menu Planning|year=2004|page=112|publisher=Juta and Company Ltd|isbn=978-0-7021-5578-9|url=http://books.google.com/?id=qhJNdB5Vw6AC&pg=PA112&dq=BMR+factors#v=onepage&q=BMR%20factors&f=false}}</ref>
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| 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.
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| [[Exergonic reaction]]s 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.
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| [[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.
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| ===Glucose===
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| 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 and six molecules of water are produced and six molecules of oxygen are consumed.
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| The overall equation for this reaction is:
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| :C<sub>6</sub>H<sub>12</sub>O<sub>6</sub> + 6 O<sub>2</sub> → 6 CO<sub>2</sub> + 6 H<sub>2</sub>O
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| Because the gas exchange in this reaction is equal, the [[respiratory quotient]] (R.Q.) for carbohydrate is unity or 1.0:
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| :R.Q. = 6 CO<sub>2</sub> / 6 O<sub>2</sub> | |
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| ===Fats===
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| 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]], [[unsaturated fat|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.
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| The overall equation for the substrate utilization of palmitic acid is:
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| :C<sub>16</sub>H<sub>32</sub>O<sub>2</sub> + 23 O<sub>2</sub> → 16 CO<sub>2</sub> + 16 H<sub>2</sub>O
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| Thus the R.Q. for palmitic acid is 0.696:
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| :R.Q. = 16 CO<sub>2</sub> / 23 O<sub>2</sub> = 0.696
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| ===Proteins===
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| 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:
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| :C<sub>72</sub>H<sub>112</sub>N<sub>18</sub>O<sub>22</sub>S + 77 O<sub>2</sub> → 63 CO<sub>2</sub> + 38 H<sub>2</sub>O + SO<sub>3</sub> + 9 CO(NH<sub>2</sub>)<sub>2</sub>
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| The R.Q. for albumin is 63 CO<sub>2</sub>/ 77 O<sub>2</sub> = 0.818
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| The reason this is important in the process of understanding protein metabolism is that 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 aerobic training session. 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.
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| 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.
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| ===Aerobic vs. anaerobic exercise===
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| Studies published in 1992<ref>{{cite journal |pmid=1550061 |year=1992 |last1=Broeder |first1=CE |last2=Burrhus |first2=KA |last3=Svanevik |first3=LS |last4=Wilmore |first4=JH |title=The effects of aerobic fitness on resting metabolic rate |volume=55 |issue=4 |pages=795–801 |journal=The American journal of clinical nutrition}}</ref> and 1997<ref>{{cite journal |pmid=9029211 |year=1997 |last1=Smith |first1=DA |last2=Dollman |first2=J |last3=Withers |first3=RT |last4=Brinkman |first4=M |last5=Keeves |first5=JP |last6=Clark |first6=DG |title=Relationship between maximum aerobic power and resting metabolic rate in young adult women |volume=82 |issue=1 |pages=156–63 |journal=Journal of applied physiology}}</ref> indicate that the level of [[Aerobic respiration|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.
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| [[Anaerobic exercise]], such as [[weight training|weight lifting]], builds additional muscle mass. Muscle contributes to the fat-free mass of an individual and therefore effective results from anaerobic exercise will increase BMR.<ref>{{cite journal |year=1986 |last1=Ravussin |first1=E |last2=Lillioja |first2=S |last3=Christin |first3=L |last4=Bogardus |first4=C |title=Determinants of 24-hour energy expenditure in man. Methods and results using a respiratory chamber |volume=78 |issue=6 |pages=1568–1578 |journal=The Journal of Clinical Invertigation |doi=10.1172/JCI112749 |last5=Bogardus |first5=C}}</ref> However, the actual effect on BMR is controversial and difficult to enumerate. Various studies<ref>{{cite journal |year=1994 |last1=Campbell |first1=W |last2=Crim |first2=M |last3=Young |first3=V |last4=Evans |first4=W |title=Increased energy requirements and changes in body composition with resistance training in older adults |volume=60 |pages=167–175 |journal=American Journal of Clinical Nutrition |pmid=8030593 |issue=2}}</ref><ref>{{cite journal |year=1994 |last1=Pratley |first1=R |last2=Nicklas |first2=B |last3=Rubin |first3=M |last4=Miller |first4=J |title=Strength training increases resting metabolic rate and norepinephrine levels in healthy 50- to 65-year-old men |volume=76 |pages=133–137 |journal=Journal of Applied Physiology |pmid=8175496 |last5=Smith |first5=A |last6=Smith |first6=M |last7=Hurley |first7=B |last8=Goldberg |first8=A |issue=1}}</ref> suggest that the resting metabolic rate of trained muscle is around 55kJ per kilogram, per day. Even a substantial increase in muscle mass, say 5 kg, would make only a minor impact on BMR.
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| Some studies{{Citation needed|date=January 2012}} suggest that a minimum of 20 to 25 minutes of cardiovascular training per day can temporarily increase the basal metabolic rate by around 10%, owing to an increase in the metabolism of the working muscles required for recovery as well as storage of glycogen and other fuel sources used by the body like ATP and Creatine.
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| ==Longevity==
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| {{See also|heartbeat hypothesis}}
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| 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 span]]s and the fact that the longevity of [[Drosophila melanogaster|fruit flies]] varies inversely with ambient [[temperature]].<ref>{{cite journal |pages=347–70 |doi=10.1016/0047-6374(76)90034-8 |title=Effects of temperature on ''the life'' span, vitality and fine structure of Drosophila melanogaster |year=1976 |last1=Miquel |first1=Jaime |last2=Lundgren |first2=Paul R. |last3=Bensch |first3=Klaus G. |last4=Atlan |first4=Henri |journal=Mechanisms of Ageing and Development |volume=5 |pmid=823384 |issue=5}}</ref> Additionally, the life span of houseflies can be extended by preventing physical activity.<ref>{{cite journal |pages=279–89 |doi=10.1016/0531-5565(75)90005-4 |title=Ambient temperature, physical activity and aging in the housefly, Musca domestica |year=1975 |last1=Ragland |first1=S.S. |last2=Sohal |first2=R.S. |journal=Experimental Gerontology |volume=10 |issue=5 |pmid=1204688}}</ref> This theory has been bolstered by several new studies linking lower basal metabolic rate to increased life expectancy, across the animal kingdom - including humans.<ref>{{cite journal |pmid=17928583 | doi=10.1152/physrev.00047.2006 | volume=87 | issue=4 | title=Life and death: metabolic rate, membrane composition, and life span of animals |date=October 2007 | author=Hulbert AJ, Pamplona R, Buffenstein R, Buttemer WA | journal=Physiol. Rev. | pages=1175–213}}</ref><ref>{{cite journal |pmid=20704872 |year=2005 |last1=Olshansky |first1=SJ |last2=Rattan |first2=SI |title=What determines longevity: Metabolic rate or stability? |volume=5 |issue=28 |pages=359–62 |journal=Discovery medicine}}</ref><ref>{{cite journal |pages=2399–406 |doi=10.1101/gad.1366505 |title=Metabolism, ubiquinone synthesis, and longevity |year=2005 |last1=Aguilaniu |first1=H. |journal=Genes & Development |volume=19 |issue=20}}</ref><ref name=pmid19837933>{{cite journal |pages=4768–75 |doi=10.1210/jc.2009-0808 |laysummary=http://www.asiaone.com/Health/News/Story/A1Story20090613-148261.html |laysource=Reuters |laydate=June 13, 2009 |title=Genetic Predisposition to Elevated Serum Thyrotropin is Associated with Exceptional Longevity |year=2009 |last1=Atzmon |first1=G. |last2=Barzilai |first2=N. |last3=Surks |first3=M. I. |last4=Gabriely |first4=I. |journal=Journal of Clinical Endocrinology & Metabolism |volume=94 |issue=12 |pmid=19837933 |pmc=2795660}}{{Unreliable medical source|date=January 2012}}</ref>
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| However, the ratio of total daily [[energy]] expenditure to resting metabolic rate can vary between 1.6 to 8.0 between species of [[mammal]]s. Animals also vary in the degree of [[Chemiosmosis|coupling between oxidative phosphorylation and ATP production]], the amount of [[saturated fat]] in mitochondrial [[Outer mitochondrial membrane|membrane]]s, the amount of [[DNA repair]], and many other factors that affect maximum life span.<ref>{{cite journal |pmid=12042467 |year=2002 |last1=Speakman |first1=JR |last2=Selman |first2=C |last3=McLaren |first3=JS |last4=Harper |first4=EJ |title=Living fast, dying when? The link between aging and energetics |volume=132 |issue=6 Suppl 2 |pages=1583S–97S |journal=The Journal of nutrition}}</ref>
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| ===Organism longevity and basal metabolic rate===
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| 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. That biomass (W) is subjected to deterioration over time from thermodynamic, entropic pressure. Metabolism is essentially understood as [[redox]] coupling, and has nothing to do with thermogenesis. Metabolic efficiency (ME) is then expressed as the efficiency of this coupling, a ratio of [[ampere]]s{{clarify|date=December 2010|reason=Why electric charge appears here out of a sudden?}} captured and used by biomass, 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.{{clarify|date=December 2010|reason=Where is MPLS in this equation? Why MR is not in watts as described one sentence earlier?}} When ME is 100%, MR = W^3/4; this is popularly known as quarter power scaling, a version of allometric scaling that is premised upon unrealistic estimates of biological efficiency.
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| 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.
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| 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.{{clarify|date=December 2010|reason=What FMR stands for?}} As ME decreases below 25%, FMR diminishes rather than increases as it does for BMR.
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| 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.{{Citation needed|date=February 2009}}
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| ==Medical considerations==
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| A person's metabolism varies with their physical condition and activity. [[Weight training]] can have a longer impact on metabolism than [[aerobic exercise|aerobic training]], but there are no known mathematical formulas that can exactly predict the length and duration of a raised metabolism from trophic changes with anabolic neuromuscular training.
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| A decrease in food intake can lower the metabolic rate as the body tries to conserve energy. Researcher Gary Foster, Ph.D., estimates that a [[very low calorie diet]] of fewer than 800 calories a day would reduce the metabolic rate by more than 10 percent.<ref name="william">Whitman, Stacy "[http://findarticles.com/p/articles/mi_m0846/is_1_23/ai_107488078/?tag=content;col1 The Truth about Metabolism]." ''Shape''. September 2003.</ref>
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| The metabolic rate can be affected by some drugs, such as [[antidepressant]]s, which may produce weight gain.<ref name="william"/> [[Antithyroid agent]]s, drugs used to treat [[hyperthyroidism]], such as [[propylthiouracil]] and [[methimazole]], bring the metabolic rate down to normal and restore [[euthyroid]]ism. Some research has focused on developing antiobesity drugs to raise the metabolic rate, such as drugs to stimulate [[thermogenesis]] in [[skeletal muscle]]. Studies of humans with 100+ year life spans have shown a link to decreased thyroid activity, their resulting lowered metabolic rate is thought to attribute to their increased life expectancy.<ref name=pmid19837933/>
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| The metabolic rate may be elevated in [[fight-or-flight response|stress]], [[illness]], and [[diabetes mellitus|diabetes]]. [[Menopause]] may also affect metabolism.
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| ==Cardiovascular implications==
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| 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]].{{Citation needed|date=April 2011}} 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,{{Citation needed|date=April 2011}} 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.{{Citation needed|date=April 2011}} This in turn leads to a lower resting heart rate, lower blood pressure, and increased resting or basal metabolic rate.{{Citation needed|date=April 2011}}
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| 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.{{Citation needed|date=April 2011}} 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.{{Citation needed|date=April 2011}} The measures of basal metabolic rate and resting metabolic rate are becoming essential tools for maintaining a healthy body weight.
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| ==See also==
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| * [[Food energy]]
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| * [[Harris-Benedict equation]]
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| * [[Hyperthyroidism]]
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| * [[Hypothyroidism]]
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| * [[Kleiber's law]]
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| * [[Metabolic age]]
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| * [[Metabolic syndrome]]
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| * [[Thermic effect of food]]
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| ==Notes==
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| {{reflist}}
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| ==References==
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| {{More footnotes|article|date=May 2012}}
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| *{{cite journal |pmid=15630109 |year=2005 |last1=Tsai |first1=AG |last2=Wadden |first2=TA |title=Systematic review: An evaluation of major commercial weight loss programs in the United States |volume=142 |issue=1 |pages=56–66 |journal=Annals of internal medicine}}
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| *{{cite journal |doi=10.1001/archinte.163.13.1524 |title=An 18-Year Follow-up of Overweight and Risk of Alzheimer Disease |year=2003 |last1=Gustafson |first1=D. |journal=Archives of Internal Medicine |volume=163 |issue=13 |pages=1524–8 |pmid=12860573 |last2=Rothenberg |first2=E |last3=Blennow |first3=K |last4=Steen |first4=B |last5=Skoog |first5=I}}
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| *{{cite journal |pmid=9771869 |year=1998 |title=Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults: Executive summary. Expert Panel on the Identification, Evaluation, and Treatment of Overweight in Adults |volume=68 |issue=4 |pages=899–917 |journal=The American journal of clinical nutrition}}
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| *{{cite journal |last1=Segal |first1=Arthur C. |title=Linear Diet Model |journal=College Mathematics Journal |volume=18 |issue=1 |pages=44–5 |year=1987 |doi=10.2307/2686315}}
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| *{{cite book |last1=Pike |first1=Ruth L |last2=Brown |first2=Myrtle Laurestine |year=1975 |title=Nutrition: An Integrated Approach |edition=2nd |location=New York |publisher=Wiley |oclc=474842663}}
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| *{{cite journal |doi=10.1046/j.1365-201X.1998.0298f.x |title=Energy supply and muscle fatigue in humans |year=1998 |last1=Sahlin |first1=K. |last2=Tonkonogi |first2=M. |last3=Soderlund |first3=K. |journal=Acta Physiologica Scandinavica |volume=162 |issue=3 |pages=261–6 |pmid=9578371}}
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| *{{cite book |last1=Saltin |first1=Bengt |last2=Gollnick |first2=Philip D. |year=1983 |chapter=Skeletal muscle adaptability: Significance for metabolism and performance |title=Handbook of Physiology |editor1-first=Lee D |editor1-last=Peachey |editor2-first=Richard H |editor2-last=Adrian |editor3-first=Stephen R |editor3-last=Geiger |location=Baltimore |publisher=Williams & Wilkins |pages=540–55 |oclc=314567389}} Republished as: {{cite book |doi=10.1002/cphy.cp100119 |chapter=Skeletal Muscle Adaptability: Significance for Metabolism and Performance |title=Comprehensive Physiology |year=2011 |last1=Saltin |first1=Bengt |last2=Gollnick |first2=Philip D. |isbn=978-0-470-65071-4}}
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| *{{cite journal |pmid=189574 |year=1976 |title=Muscle strength, fibre types and enzyme activities in man |volume=443 |pages=1–45 |journal=Acta physiologica Scandinavica. Supplementum |author=Thorstensson}}
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| *{{cite journal |doi=10.1111/j.1748-1716.1977.tb10373.x |title=Actomyosin ATPase, Myokinase, CPK and LDH in Human Fast and Slow Twitch Muscle Fibres |year=1977 |last1=Thorstensson |first1=Alf |last2=Sjödin |first2=Bertil |last3=Tesch |first3=Per |last4=Karlsson |first4=Jan |journal=Acta Physiologica Scandinavica |volume=99 |issue=2 |pages=225–9 |pmid=190869}}
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| *{{cite journal |doi=10.1007/BF02337175 |title=Hormonal and metabolic response to three types of exercise of equal duration and external work output |year=1985 |last1=Vanhelder |first1=W. P. |last2=Radomski |first2=M. W. |last3=Goode |first3=R. C. |last4=Casey |first4=K. |journal=European Journal of Applied Physiology and Occupational Physiology |volume=54 |issue=4 |pages=337–42 |pmid=3905393}}
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| *{{cite journal |pmid=13405829 |year=1957 |last1=Wells |first1=JG |last2=Balke |first2=B |last3=Van Fossan |first3=DD |title=Lactic acid accumulation during work; a suggested standardization of work classification |volume=10 |issue=1 |pages=51–5 |journal=Journal of applied physiology}}
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| *{{cite book |last1=McArdle |first1=William D |last2=Katch |first2=Frank I |last3=Katch |first3=Victor L |year=1986 |title=Exercise Physiology: Energy, Nutrition, and Human Performance |publisher=Lea & Febiger |location=Philadelphia |oclc=646595478}}
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| ==External links==
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| *{{cite journal |pmid=16576330 |year=1918 |last1=Harris |first1=JA |last2=Benedict |first2=FG |title=A Biometric Study of Human Basal Metabolism |volume=4 |issue=12 |pages=370–3 |pmc=1091498 |journal=Proceedings of the National Academy of Sciences of the United States of America |doi=10.1073/pnas.4.12.370|bibcode = 1918PNAS....4..370H }}
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| * [http://chla.library.cornell.edu/cgi/t/text/pageviewer-idx?c=chla;cc=chla;sid=c42d310a7654d488f3e2ae6f21e7be0d;rgn=full%20text;idno=2905932;view=image;seq=0001 Harris-Benedict study. Detailed discussion of antecedents, data, measurements, statistics (Published by The Carnegie Institution of Washington 1919)]
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| * [http://www.danoneinstitute.org/objective_nutrition_newsletter/on45.php BMR as affected by alcohol]
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| * [http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0054746 BMR and personality]
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| * [http://toast99.com/Calculator/BMR Implementation of The Mifflin St Jeor Equation]
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| {{DEFAULTSORT:Basal Metabolic Rate}}
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| [[Category:Exercise physiology]]
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| [[Category:Metabolism]]
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