RESUMO
The energetic metabolism and its relationship with body weight generated a vivid controversy, since the Rubner's surface law was introduced into biology. Recently, the multifactor theory (Darveau et al) has caused again a revival of this polemic topic. Moreover, the investigations concerning metabolism and body weight include all terrestrial mammals, from the shrew (3 grams) to the elephant (three tons). The corresponding allometric exponent for standard metabolic rate, both theoretical and empirical, fluctuates around an average value of 0.75, in contrast with the surface law, which postulated a value of 0.67. The "metabolic range" (rest vs maximal exercise) does vary from 1 to 10, due to the prevalent influence of the skeletal muscle activity. Recent investigations have emphasized the fact that the allometric exponent is not unique (0.75), but it should be subjected to statistical variability, both in standard and in maximal exercise.
Assuntos
Humanos , Animais , Exercício Físico/fisiologia , Estresse Oxidativo , Homeostase , Metabolismo Basal/fisiologia , Consumo de Oxigênio , Peso Corporal , Teste de EsforçoRESUMO
The clinical applications of standarized physiological functions such as cardiovascular, respiratory and renal systems are discussed
Assuntos
Humanos , Animais , Sistema Cardiovascular/fisiologia , Padrões de Referência , Sistema Respiratório/fisiologia , Superfície Corporal , Consumo de Oxigênio/fisiologia , Hemodinâmica/fisiologia , Monitorização FisiológicaRESUMO
Since Rubner stablished in 1883 the surface law, the basal metabolic rate (kcal/24h) is expressed per square meter of body surface. This so-called biological law has been extrapolated to the standarization of several other functions as, for instance, to variables of the cardiovascular, respiratory and renal systems, which may lead to erroneous conclusions. The present paper is an attempt to establish, by means of the dimentional analysis and one of the theories of biological similarity, an allometric indexation procedure, which yields mass-independent numbers (MIN) for all functions which can be defined by means of the MLT system of physics (Mass; Length; Time)