Energy Balance and Body Composition Weight Control: Overweight and Underweight Flashcards
Energy Balance
Negative
Positive
Energy Metabolism
Definition: Energy metabolism is defined as the ___ ___ of all____ reactions that manage _____ ____ ____ (___ ___ ___) in the body.
Definition: Energy metabolism is defined as the sum total of all chemical reactions that manage energy-yielding nutrients (carbohydrates, proteins, and lipids) in the body.
Energy Balance: A Practical Representation
Energy balance (equilibrium)
Positive energy balance
Negative energy balance
Energy Balance
1 lb of fat = ____ kcal
One pound of fat = 3500 kcal.
Factors that Influence Food Intake
A. Short-term regulation
B. Long-term regulation: A_____mechanism has been proposed involving a signal from the ___ ___ that is released when “___” ___ ____is disturbed. This factor may play a role primarily in ____ persons, as opposed to the elderly.
A. Short-term regulation
q Hunger
q Appetite
q Satiation
q Satiety
q Nutrients, Satiation, and Satiety
q Role of hypothalamus
B. Long-term regulation: A feedback mechanism has been proposed involving a signal from the adipose mass that is released when “normal” body composition is disturbed. This factor may play a role primarily in younger persons, as opposed to the elderly.
Hunger
q The ___ ___for food that initiates___ ____ ___
q The physiological drive for food that initiates food-seeking behavior.
Appetite
q The integrated response to the___ ___ ___ or ____of food that ____ or ___ ____
q The integrated response to the sight, smell, thought, or taste of food that initiates or delays eating.
Satiation
The feeling of _______________that occurs ____a meal and ___ ____ Satiation determines how much
q The feeling of satisfaction and fullness that occurs during a meal and halts eating. Satiation determines how much food is consumed during a meal.
Satiety
q The feeling of satisfaction that occurs ____ a meal and________________, Satiety determines how much ____________________
q The feeling of satisfaction that occurs after a meal and inhibits eating until the next meal. Satiety determines how much time passes between meals.
Nutrients, Satiation, and Satiety
q The extent to which foods produce satiation and sustain satiety depends in part on the ____ _____ of a meal. Of the three energy-yielding nutrients,_____ is the most satiating.
q The extent to which foods produce satiation and sustain satiety depends in part on the nutrients composition of a meal. Of the three energy-yielding nutrients, protein is the most satiating.
Hypothalamus: A Satiety Regulator
q A brain center that controls activities such as ______ ______ _____
q A brain center that controls activities such as maintenance of water balance, regulation of body temperature, and control of appetite.
Conversion of Food Energy
v The body converts the energy of food to the energy currency of ___ molecules with about ___% efficiency, radiating the rest as ____. Then, when ATP is ___ to ___ ___, again about __% is lost as heat. Thus, the overall efficiency of the human body in converting food energy to work is __%, the other ___% is released as heat. The work itself, as it is, reflects the amount of energy it is spending.
v The body’s___ ___ ____is known as “thermogenesis”, and it can be measured to determine the amount of ____
v The body converts the energy of food to the energy currency of ATP molecules with about 50% efficiency, radiating the rest as heat. Then, when ATP is used to do work, again about 50% is lost as heat. Thus, the overall efficiency of the human body in converting food energy to work is 25%, the other 75% is released as heat. The work itself, as it is, reflects the amount of energy it is spending.
v The body’s generation of heat is known as “thermogenesis”, and it can be measured to determine the amount of energy it is spending.
Thermogenesis
The ___of ___; used in ___ and ____ studies as an ___ of how much ___ the ___ is ____.
The generation of heat; used in physiology and nutrition studies as an index of how much energy the body is spending.
Three Categories of Thermogenesis
_____
____
______
Ø Basal thermogenesis (metabolism)
ØBasal metabolism
Ø Exercise-induced thermogenesis (physical activity)
Ø Diet-induced thermogenesis (thermic effect of food)
Measurement of Energy
___
___
unit of measure
___ ___ value
[*] Direct calorimetry
[*] Indirect calorimetry
[*] Unit of measurement: kcal
[*] Physiological fuel value
Direct Calorimetry
Direct calorimetry ___ the ___ ___ as ___ ___
vBomb calorimeter: An instrument that measures the ___ ___ when foods are ___ ___
Direct calorimetry measures the energy output as heat energy.
vBomb calorimeter: An instrument that measures the heat released when foods are combusted completely.
Indirect Calorimetry
\The ____ of energy output from measures of the amount of____ and ____
The estimation of energy output from measures of the amount of oxygen used and carbon dioxide eliminated.
Basal Metabolism
The ____ needed to maintain life when the body is at ___ ___ after a __-hour fast.
[*] Basal metabolic rate (BMR): The __ of ___ used for ___ under ____conditions, usually expressed as ____________
[*] ____ ___ ____(REE) is similar to basal metabolic rate, but the criteria for rest and fasting are ____ strict ( the difference between BMR and REE is less than __%).
[*] Basal metabolism represents the ____ component (___-__% of energy expenditure).
The energy needed to maintain life when the body is at complete rest after a 12-hour fast.
[*] Basal metabolic rate (BMR): The rate of energy used for metabolism under basal conditions, usually expressed as kcalories per kilogram body weight per hour.
[*] Resting energy expenditure (REE) is similar to basal metabolic rate, but the criteria for rest and fasting are less strict ( the difference between BMR and REE is less than 10%).
[*] Basal metabolism represents the largest component (60-65% of energy expenditure).
Factors That Increase Basal Metabolic Rate (BMR)
___ Caff
___Hormone
____Environ T
____Fever
___ Smok
__ Body comp
___ Pregnancy
___ Growth
vGrowth: when child is growing BMR is high per kg. they grow very rapidly first year
vPregnancy: state of high BMR . Create all extra tissue so need high
vHormones: thyroid hormones increase. If you don’t make enough thyroxin you will feel tiredà hypothyrodism
vSmoking: quit smoking, gain weight
vCaffeine:
vEnvironmental temperature: every degree T goes up, increases BMR
vFever:
vBody composition: muscle mass is really influencing BMR. As we get older this muscle mass decreases and decreases BMR
Factors That Decrease Basal Metabolic Rate (BMR)
_ Fasting
_Malnutrition
_ Age
_ Starvation
_ Sleep
Important Factors Related to BMR
vLean body mass (muscle mass)___ with ____,_____ the BMR.
vBMR begins to decrease in ___ ____ at a rate of about _% per ____.
vBMR is slower in ____ individuals due to
vLean body mass (muscle mass) diminishes with age, slowing the BMR.
vBMR begins to decrease in early adulthood at a rate of about 2% per decade.
vBMR is slower in malnourished individuals due to loss of lean body mass.
Thermogenisis types
Basal metab> physical activity> thermic effect of food
Thermic Effect of Food
qThermic effect (___) – The ____ in metabolism occurring during the ___ ___ and ____ of energy-yielding nutrients. This represents __-__% of energy consumed.
qThermic effect (TEF) – The increase in metabolism occurring during the digestion, absorption, and metabolism of energy-yielding nutrients. This represents 5-10% of energy consumed.
Estimating Energy Requirements
1.
2
3
These three factors are influenced by a persons __ __ ____ ____ ____
1.Calculation of daily energy needs:
A. Basal metabolism
B. Physical activity
C. Thermic effect
• These three factors are influenced by a person’s age, sex, body size, genes, health status, etc.
