 Energy requirement varies with environmental
conditions
 The rate at which the body uses energy while at rest to
maintain a vital functions such as breathing and keeping
warm
Condition
Awake but complete rest – physical /mental
Fasting at least 12 – 18 hours – post absorption state

 Post absorptive state allowed to avoid
 Effect of digestion and absorption
Prevent any chance of starvation
3] remain in normal living condition temperature
, pressure and humidity 20 - 25

 Under the condition the energy expendicture is only on
 Respiration
 Circulation
 Muscle tone [skeletal and smooth muscles ]
 Function of viscera [kidney ,liver and brain]

 Basal metabolism refers to amount of energy required
to
 1.eat dinner
 2. carry out all the vital process
 3. run a marathon
 4. keep heart beating
 Heat is given off by a subject who though awake is lying
in a state of maximum physical and mental rest under
comfortable condition of temperature pressure ,
humidity and 12- 18 hours post absorptive state

 Energy produced , under such basal condition per unit
time and per sq. meter of body surface area is known as
basal metabolic rate
 It is the minimum amount of energy required to
maintain life
 BMR of a sleeping person is lower than awake person
 Measured
directly by the heat evolved
indirectly by the volume of oxygen consumed and
carbon dioxide /unit time

 The rate of metabolism at basal condition has
found to vary in different individuals due to
different factors

 The BMR of children is much higher than adults
 Is low in old age

 Women normally have a lower BMR than men
 BMR of females decline between the ages of 5 and 17 more
rapidly than those of males

 In cold climate BMR is a compensatory
mechanism to maintain body temperature

 BMR is high in febrile state
 12 percent rise is found associated with 1˚C
rise in temperature

 BMR is low in condition of malnutrition ,
starvation and wasting disease

 Athelets ,soldiers and manual workers have
a slight higher in BMR than leading
sedentary workers

 Age , gender ,body size and climate determine
the ;
Growth rate of an individual
Basal metabolic rate
pressure influence on growth rate

 Quite number of drugs like
caffeine
Benzedrine
epinephrine
nicotine
alcohol, increase the BMR

Thank you