Energy Balance

Question 1

What is energy balance?

Answer 1

relationship between energy intake and energy expenditure

Question 2

What is positive energy balance?

Answer 2

weight gain

Question 3

when is positive energy balance desired?

Answer 3

during growth stages (pregnancy, infancy, childhood, adolescence) or when body weight needs to be restored (after starvation, disease, injury)

Question 4

what is negative energy balance?

Answer 4

weight loss

Question 5

When does negative energy balance occur?

Answer 5

when energy stored in the body (fat, muscles) is used to make up for shortfall in energy intake

Question 6

when is negative energy balance desired?

Answer 6

in adults when body fat exceeds healthy levels

Question 7

What is the dynamic equilibrium between that body weight results from?

Answer 7

energy intake (EI) and energy expenditure (EE)

Question 8

What is the first law of thermodynamics?

Answer 8

energy can be neither created nor destroyed

Question 9

what are the two types of units of measure under the first law?

Answer 9

kilocalorie (kcal) and kilojoule (kJ)

Question 10

What is a kilocalorie (kcal)?

Answer 10

heat required to raise the temp of one kg of water by one degree C

Question 11

What is a kilojoule (kJ)?

Answer 11

force required to move one kg, one meter with a force of 1 newton

Question 12

how many kJ does 1 kcal equal?

Answer 12

4.184 kJ

Question 13

how can the amount of energy in a food or beverage can be estimated?

Answer 13

using nutrient databases or nutrient analysis software

Question 14

how is the calorie content most commonly calculated?

Answer 14

as grams of carbohydrates, protein, and fat in a food multiplied by physiological fuel value of these compounds

Question 15

how does a bomb calorimeter measure the calorie content?

Answer 15

by burning (combustion = process of burning) a dried portion of food

Question 16

why is nitrogen converted to energy?

Answer 16

because oxygen gas is involved in formation of nitric acid in a bomb calorimeter

Question 17

what is the physiological fuel value for carbs?

Answer 17

4

Question 18

What is the physiological fuel value for fat?

Answer 18

9

Question 19

What is the physiological fuel value for protein?

Answer 19

4

Question 20

what is the physiological fuel value for alcohol?

Answer 20

7

Question 21

What are the 3 main purposes the body uses energy?

Answer 21

basal metabolism (BMR); physical activity; digestion, absorption, processing of ingested nutrients

Question 22

What is the basal metabolism (BMR)?

Answer 22

energy required, at rest, to maintain life

Question 23

What does the BMR represent?

Answer 23

the minimum amount of energy expended in a fasting state (12 hrs or more) to keep a resting, awake body alive in a warm quiet environment

Question 24

how much does BMR account for of a total energy expenditure for a sedentary person

Answer 24

60-70%

Question 25

what is a key regulator of BMR?

Answer 25

thyroid hormones

Question 26

What are factors influencing BMR?

Answer 26

body size (larger body surface increases BMR), body composition (greater muscle mass increases BMR), gender (men have more muscles and bigger body surface; thus higher BMR), age (aging after 30 years decreases BMR), body temp (fever or cold environment conditions increases BMR), sleep, undernutrition (malnutrition lowers BMR), hormones (higher than normal secretion of thyroid hormones or release of stress hormones will increase BMR), smoking and caffeine use will increase BMR

Question 27

what would 30 minutes of moderate physical activity reduce?

Answer 27

the risk of developing a chronic disease

Question 28

What would up to 60 minutes of exercise on most days do?

Answer 28

avoid unhealthy weight gain

Question 29

how much physical activity is needed to sustain weight loss?

Answer 29

at least 60-90 minutes

Question 30

how much does physical activity increase energy expenditure above and beyond basal energy needs?

Answer 30

by as much as 25-40%

Question 31

how is energy expenditure determined?

Answer 31

by direct or indirect calorimetry

Question 32

what is another name for thermic effect of food (TEF)?

Answer 32

diet induced thermogenesis (DIT)

Question 33

how much of the energy consumed each day does TEF account for?

Answer 33

5-10%

Question 34

what is obligatory thermogenesis?

Answer 34

unavoidable losses due to absorption, transport, storage, synthesis of protein, fat, etc.

Question 35

What is facultative thermogenesis?

Answer 35

futile heat-releasing reactions and activity of nervous system

Question 36

why is the TEF for protein-rich meals higher than carbohydrate-rich or fat-rich meals?

Answer 36

it takes more energy to metabolize amino acids into fat than to convert glucose into glycogen or transfer absorbed fat into adipose stores

Question 37

do larger or smaller meals result in higher TEF values

Answer 37

larger

Question 38

what does NEAT stand for?

Answer 38

non-exercise activity thermogenesis

Question 39

how is NEAT stimulated?

Answer 39

by cold environment or overeating (in some)

Question 40

what are examples of NEAT?

Answer 40

shivering, fidgeting, muscle tone, posture

Question 41

what is a form of fat that participates in thermogenesis

Answer 41

brown adipose tissue

Question 42

where does brown adipose tissue get its brown appearance?

Answer 42

from the large number of capillaries

Question 43

why does brown adipose tissue contribute to thermogenesis?

Answer 43

because it releases much of the energy from energy-yielding nutrients as heat

Question 44

T/F: brown adipose tissue has a protein that uses the food we consume to generate heat for the body instead of creating energy in the form of ATP

Answer 44

true

Question 45

who is brown adipose tissue mostly found?

Answer 45

in infants (5% of body weight) and hibernating animals (to generate heat during cold winters)

Question 46

what is the rule of thumb of estimates of energy use in a sedentary lifestyle?

Answer 46

12 /14 kcal/lb (women/men)

Question 47

what is the rule of thumb of estimates of energy use in a moderate activity lifestyle

Answer 47

15/17 kcal/lb (women/men)

Question 48

What is the rule of thumb of estimates of energy use in a active lifestyle?

Answer 48

18/20 kcal/lb (women/men)

Question 49

what is the harris-benedict equation used for?

Answer 49

method used to estimate BMR and daily kcal requirement for an individual

Question 50

what is the harris-benedict equation?

Answer 50

BMR=kcal/d=66.5 + (13.8 x weight in kg) + (5 x height in cm) - (6.8 x age in yr)

Question 51

what is the rda for energy in a active 19 yr?

Answer 51

3067/2403 kcal/d (men/women)

Question 52

what does direct calorimetry estimate?

Answer 52

EE by measuring the amount of body heat released by a person

Question 53

how does all energy the body use leave?

Answer 53

as heat

Question 54

the heat released from a body is measured how?

Answer 54

by placing a person in an insulated chamber (size of a bedroom) that is surrounded by a layer of water

Question 55

what is used to determine the amount of energy the person expended?

Answer 55

the change in water temperature before and after exercise

Question 56

what does indirect calorimetry involve?

Answer 56

collecting expired air from an individual during a specific amount of time

Question 57

T/F: indirect calorimetry must be done in a clinical setting

Answer 57

FALSE, can be done at home!

Question 58

what is doubly labeled water?

Answer 58

subject is given an oral dose of water containing the isotopes 2H (deuterium) and 18O, and then his/her urine and blood samples are analyzed to examine both isotopes excretion

Question 59

how can you measure EE?

Answer 59

non-calorimetric methods (heart rate monitor & accelerometers) and predictive equations