Difference between revisions of "Body mass"

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{{MitoPedia
 
{{MitoPedia
 
|abbr=''M'' [kg·x<sup>-1</sup>]
 
|abbr=''M'' [kg·x<sup>-1</sup>]
|description=The '''body mass''', ''M'', is the mass [kg] of an individual (object) [x] and is expressed in units [kg/x]. The individual (object) is a countable quantity, therefore, the unit [x] is a dimensionless number. The SI unit for mass (of a system), ''m'', is [kg] (1 kg = 1000 g). A system is not a countable quantity and thus is not a number. Both, body mass [kg/x] and mass of a system [kg] are [[Extensive quantity |extensive quantities]], which depend on the size of the individual or the system. Whereas the body weight changes as a function of gravitational force (you are weightless at zero gravity; your floating weight in water is different from your weight in air), your mass is independent of gravitational force, and it is the same in air and water.
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|description=The '''body mass''', ''M'', is the mass [kg] of an individual (object) [x] and is expressed in units [kg/x]. The individual (object) is a countable quantity, therefore, the unit [x] is a dimensionless number. The SI unit for mass (of a system), ''m'', is [kg] (1 kg = 1000 g). A system is not a countable quantity and thus is not a number. The SI symbol ''m'' is used to indicate the mass of a system [kg], whereas the symbol ''M'' is used to indicate the mass of an individual (object) [kg·x<sup>-1</sup>]. Both, body mass [kg/x] and mass of a system [kg] are [[Extensive quantity |extensive quantities]], which depend on the size of the individual or the system. Whereas the body weight changes as a function of gravitational force (you are weightless at zero gravity; your floating weight in water is different from your weight in air), your mass is independent of gravitational force, and it is the same in air and water.
 
The total body mass is the sum of lean body mass and fat mass, ''M'' = ''M''<sub>L</sub> + ''M''<sub>F</sub>, or the sum of the reference body mass of the [[healthy reference population]] and excess body mass, ''M'' = ''M''° + ''M''<sub>E</sub>. The excess body mass, in turn, is the sum of excess lean and [[Body fat excess |fat mass]], ''M''<sub>E</sub> = ''M''<sub>LE</sub> + ''M''<sub>FE</sub>. The [[body mass excess]], BME, is normalized for the reference body mass, BME = ''M''/''M''°.
 
The total body mass is the sum of lean body mass and fat mass, ''M'' = ''M''<sub>L</sub> + ''M''<sub>F</sub>, or the sum of the reference body mass of the [[healthy reference population]] and excess body mass, ''M'' = ''M''° + ''M''<sub>E</sub>. The excess body mass, in turn, is the sum of excess lean and [[Body fat excess |fat mass]], ''M''<sub>E</sub> = ''M''<sub>LE</sub> + ''M''<sub>FE</sub>. The [[body mass excess]], BME, is normalized for the reference body mass, BME = ''M''/''M''°.
 
|info=[[Gnaiger 2019 MitoFit Preprint Arch]], [[Gnaiger 2019 MiP2019]]
 
|info=[[Gnaiger 2019 MitoFit Preprint Arch]], [[Gnaiger 2019 MiP2019]]

Revision as of 19:32, 15 January 2020

Bioblasts - Richard Altmann and MiPArt by Odra Noel
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Body mass

Description

The body mass, M, is the mass [kg] of an individual (object) [x] and is expressed in units [kg/x]. The individual (object) is a countable quantity, therefore, the unit [x] is a dimensionless number. The SI unit for mass (of a system), m, is [kg] (1 kg = 1000 g). A system is not a countable quantity and thus is not a number. The SI symbol m is used to indicate the mass of a system [kg], whereas the symbol M is used to indicate the mass of an individual (object) [kg·x-1]. Both, body mass [kg/x] and mass of a system [kg] are extensive quantities, which depend on the size of the individual or the system. Whereas the body weight changes as a function of gravitational force (you are weightless at zero gravity; your floating weight in water is different from your weight in air), your mass is independent of gravitational force, and it is the same in air and water. The total body mass is the sum of lean body mass and fat mass, M = ML + MF, or the sum of the reference body mass of the healthy reference population and excess body mass, M = M° + ME. The excess body mass, in turn, is the sum of excess lean and fat mass, ME = MLE + MFE. The body mass excess, BME, is normalized for the reference body mass, BME = M/M°.

Abbreviation: M [kg·x-1]

Reference: Gnaiger 2019 MitoFit Preprint Arch, Gnaiger 2019 MiP2019

Contributed by Gnaiger E (2020-01-15)

Human body mass

The body mass of a human is measured without outdoor clothing (in light underware or swimsiut and without shoes) standing upright on a firm horizontally leveled and calibrated balance. This SOP applies to mobile persons who can stand steadily for the measurement. Some studies apply rigorous standards: 'All measurements were done at least 3 h after a meal (including drink), and subjects were requested to refrain from strenuous exercise 12 h prior to the measurements. Subjects were asked to empty their bladder before the measurements. Females were not measured during their menstrual period' (Deurenberg 2001 Eur J Clin Nutr).

Self-reported measurements

'Men overestimated their height by 1.3 to 1.9 cm and the women by 0.5 to 1.3 cm. Men overestimated their weight by up to 0.45 kg and women underestimated their weight by up to 1.4 kg' (Tipton 2012 Nursing).


MitoPedia: BME

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MitoPedia: BME

TermAbbreviationDescription
BME and mitObesity
BME cutoff pointsBME cutoffCutoff points for body mass excess, BME cutoff points, define the critical values for underweight, overweight, obesity and various degrees of obesity. BME cutoffs are calibrated by crossover-points of BME with established BMI cutoffs. The underweight and severe underweight cutoff points are BME = -0.1 and -0.2. The overweight cutoff is BME = 0.2. Increasing degrees of obesity are defined by BME cutoffs of 0.4, 0.6, 0.8, and above.
Body fat excessBFEBody fat is conventionally expressed as BF%, which is the percentage of body fat mass relative to the total body mass. In the healthy reference population (HRP), there is zero body fat excess, and the fraction of excess body fat in the HRP is expressed - by definition - relative to the reference body mass, M°, at any given height. Although M° is identical in females and males at any given height, the fraction of body fat is higher in females than males in the HRP, hence it is reasonable that the body fat excess, BFE, - but not BF% - represents the common risk factor and indicator of obesity. Importantly, body fat excess and body mass excess, BME, are linearly related, which is not the case for the body mass index, BMI.
Body massM [kg·x-1]The body mass, M, is the mass [kg] of an individual (object) [x] and is expressed in units [kg/x]. The individual (object) is a countable quantity, therefore, the unit [x] is a dimensionless number. The SI unit for mass (of a system), m, is [kg] (1 kg = 1000 g). A system is not a countable quantity and thus is not a number. The SI symbol m is used to indicate the mass of a system or sample [kg], whereas the symbol M is used to indicate the mass of an individual (object) [kg·x-1]. Both, body mass [kg/x] and mass of a sample [kg] are extensive quantities, which depend on the size of the individual or the sample. Whereas the body weight changes as a function of gravitational force (you are weightless at zero gravity; your floating weight in water is different from your weight in air), your mass is independent of gravitational force, and it is the same in air and water. The total body mass is the sum of lean body mass and fat mass, M = ML + MF, or the sum of the reference body mass of an individual at a given height in the healthy reference population and excess body mass, M = M° + ME. The excess body mass, in turn, is the sum of excess lean and fat mass, ME = MLE + MFE. The body mass excess, BME, is normalized for the reference body mass, BME = M/M°.
Body mass excessBMEThe body mass excess, BME, is a lifestyle metric. The BME with respect to the healthy reference population, HRP, is defined as BME ΔM/M°. ΔM is the excess body mass exceeding the reference body mass, M°, in the HRP. Thus the BME is a measure of the extent to which your actual body mass, M [kg/x], deviates from M° [kg/x], which is the reference body mass [kg] per individual [x] without excess body fat. The BME is expressed relative to the reference body mass for your height, H [m]. A balanced BME is BME° = 0.0 with a band width of -0.1 towards underweight and +0.2 towards overweight. Considering a height of 1.78 m, the balanced body mass is M° = 65.9 kg per individual, and overweight is reached at a weight gain of 20 % or BME = 0.2: (1+0.2)·M° = 79 kg per individual (body mass index BMI0.2 = 24.9 kg/m2). At a height of 1.84 m, the balanced body mass is M° = 72.4 kg/x, and obesity is reached at a weight gain of 40 % or BME = 0.4:(1.4·M° = 101.4 kg/x (BMI0.4 = 29.9 kg/m2).
Gnaiger 2019 MiP2019
Healthy reference populationHRPA healthy reference population, HRP, of zero underweight or overweight is considered as a standard population. The WHO Child Growth Standards on height and body mass are based on large samples in longitudinal (N=1737 children) and cross-sectional studies (N=6669) with similar numbers of girls and boys from Brazil, Ghana, India, Norway, Oman and the USA (1997-2003). Anthropometric studies carried out on adults since the 1960ies are prone to reflect the impact of high-caloric nutrition on allometric relationships, referring us to earlier time points for a HRP. The Committee on Biological Handbooks compiled a large dataset on height and body mass of healthy males from infancy to old age (CBH dataset, N=17523; Zucker 1962). The original studies were published between 1931 and 1944 and thus apply to a population (USA) before emergence of the fast-food and soft drink epidemic, and with a lifestyle demanding a balanced physical activity without the impact of local war or economic disaster on starvation.
Height of humansH [m]The height of humans, H, is given in SI units in meters [m]. Without further identifyer, H is considered as the standing height, measured without shoes, hair ornaments and heavy outer garments. The person is standing upright on a firm horizontally leveled surface. A small gap of 0.1 m (10 cm) is maintained between the heels of the feet which face straight ahead and arms at sides. The back of the head, shoulder blades, buttocks and heels are touching the wall-mounted statiometer. For facing straingt, the ear canal and cheek bone are level. The 90° head of the statiometer is lowered to press the hair flat. This SOP applies to mobile persons who can stand steadily for the measurement.
VO2maxVO2max; VO2max/MMaximum oxygen consumption, VO2max, is measured by spiroergometry on human and animal organisms capable of controlled physical exercise performance on a treadmill or cycle ergometer. VO2max is the maximum respiration of an organism, expressed as the volume of O2 at STPD consumed per unit of time per individual object [mL.min-1.x-1]. If normalized per body mass of the individual object, M [kg.x-1], mass specific maximum oxygen consumption, VO2max/M, is expressed in units [mL.min-1.kg-1]. For conversion to SI units of amount of oxygen consumed, VO2max is multiplied by the conversion factor of 0.744 to obtain JO2max [µmol O2∙s-1.x-1].


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