Energy Balance and Body Composition

Question 1

Energy balance (energy equilibrium)

Answer 1

intake matches expenditure

Question 2

positive energy balance

Answer 2

intake exceeds expenditure

Question 3

negative energy balance

Answer 3

intake is less than expenditure

Question 4

What does the body use energy for?

Answer 4

1. basal metabolic rate
2. physical activity
3. thermic effect of food (digestion, absorption, processing of ingested nutrients)

Question 5

Thermogenesis

Answer 5

minor form of energy output

shivering, fidgeting

Question 6

Basal metabolic rate

Answer 6

amount of energy required in a fasting state to keep the resting body functioning

Question 7

largest component of energy expenditure

Answer 7

basal metabolic rate (BMR)

Question 8

What three organs in the body use the most amount of energy when a person is at rest?

Answer 8

1. liver (27%)
2. brain (19%)
3. skeletal muscle (18%)

Question 9

basal metabolic rate (amount of total energy expenditure)

Answer 9

60-70%

Question 10

resting metabolic rate (RMR)

Answer 10

when a person is not fasting or resting (about 6% higher than BMR)

Question 11

BMR and RMR and their respective numbers for women and men

Answer 11

of calories burned per unit of time
women- 0.9 kcal/kg per hour
men- 1.0 kcal/kg per hour

Question 12

Factors that increase BMR

Answer 12

• muscle mass
• body surface area
• male gender
• body temperature
• secretions of thyroid hormone (hyperthyroidism)
• stress hormones

Question 13

factors that may decrease BMR

Answer 13

• hypothyroidism
• restricted calorie intake
• less muscle mass/body surface area
• aging declines 1-2% each decade after age 30

Question 14

Physical activity energy expenditure

Answer 14

• increases kcal needs by 25-40% above BMR

Question 15

thermic effect of food energy expenditure

Answer 15

• accounts for 5-10% of kcal consumed daily
• digest, absorb, transport, store, and metabolize
• varies by nutrient content! (highest for protein)

Question 16

Adaptive thermogenesis energy expenditure

Answer 16

• contributes a small amount

- triggered by the cold, overfeeding, trauma, starvation

Question 17

what is non-voluntary physical activity/non-exercise activity thermogenesis (NEAT)?

Answer 17

fidgeting, shivering, holding the body upright

Question 18

Adaptive thermogenesis- what may it be dependent on?

Answer 18

brown adipose tissue

- limited in adults (infants/hibernating animals have more of it)

Question 19

Direct calorimetry

Answer 19

measuring the amount of heat released by the body (estimates energy expenditure)

• change in temperature determines the amount of energy the person expended
• expensive and complex

Question 20

indirect calorimetry

Answer 20

collects the air expired during a specified time period

- oxygen consumed? carbon dioxide produced?

Question 21

estimated energy requirements (EER)

Answer 21

based on evidence gathered through direct and indirect calormetry

Question 22

EER needs based on?

Answer 22

• weight
• height
• sex
• age
• physical activity level

Question 23

Hunger

Answer 23

physiological drive to find and eat food

- controlled by internal mechanisms (organs, hormones, nervous system, hormone-like factors)

Question 24

appetite

Answer 24

psychological drive to eat

- impacted by external factors

Question 25

Satiety

Answer 25

feeling of fullness following the consumption of food

Question 26

what suppresses further consumption and influences time between meals?

Answer 26

satiety

Question 27

what eating behavior regulation is regulated by the hypothalamus?

Answer 27

satiety

Question 28

job of hypothalamus

Answer 28

- communicates with the endocrine system/nervous system

Question 29

how does the hypothalamus integrate internal cues?

Answer 29

- blood glucose levels - hormone secretions - sympathetic nervous system

Question 30

satiation

Answer 30

causes us to stop eating

Question 31

what hormones are secreted to promote satiation?

Answer 31

- CCK - glucagon-like-peptide-1 - peptide YY

Question 32

what promotes satiety (occurs after eating has stopped)?

Answer 32

- sensory aspects - knowledge of consumption - chewing - expansion of stomach/intestines - effects of digestion/absorption/metabolism - decrease in ghrelin

Question 33

hormones that play a role in the regulation of hunger and satiety?

Answer 33

- ghrelin | - leptin

Question 34

ghrelin

Answer 34

- hypothalamus | - increases appetite, smell sensitivity, energy storage is promoted

Question 35

leptin

Answer 35

- hypothalamus - signals the brain to decrease intake - rises when body fat increases

Question 36

leptin deficiency leads to what?

Answer 36

constant hunger

Question 37

what is long-term satiety promoted by?

Answer 37

body composition/amount of body fat

Question 38

what is leptin secreted by?

Answer 38

adipose tissue (increase in adipose storage= increase in leptin levels)

Question 39

when do satiety signals diminish?

Answer 39

several hours after eating (stored energy use begins)

Question 40

what hormones stimulate appetite and increase intake?

Answer 40

cortisol and ghrelin

Question 41

methods to assess weight status

Answer 41

- total body fat - location of body fat - weight-related medical complications

Question 42

body mass index

Answer 42

- height to weight standard - linked to body fat content and longevity - body fat influences health more than body weight

Question 43

BMI categorization

Answer 43

underweight (<18.5) healthy weight (18.5-24.9) overweight (25-29.9) obesity (greater than or equal to 30)

Question 44

BMI complications

Answer 44

- not appropriate for children, teens, older adults, and pregnant/lactating women - those with high levels of tissue/less than 5 feet tall may have inaccurate categorization

Question 45

methods to measure body composition

Answer 45

- underwater weighing - air displacement - skinfold thickness - bioelectrical impedance - dual energy XRAY absorptiometry (DXA)

Question 46

underwater weighing

Answer 46

body weight measured under water and in air

Question 47

air displacement

Answer 47

determines body volume by measuring the volume of air displaced when a person sits in a sealed chamber for a few minutes

Question 48

skinfold thickness

Answer 48

measure fat layer directly under skin at multiple sites (not as accurate)

Question 49

bioelectrical impedance

Answer 49

- electrical current sent through body - short duration - fat resists flow of electricity more than lean tissue

Question 50

DXA

Answer 50

- MOST ACCURATE - expensive - body fat, fat-free soft tissue, and bone minerals assessed

Question 51

desirable body fat for men and women respectively

Answer 51

men - 8 to 24% | women- 21 to 35% (reproductive function leads to increased levels of body fat)

Question 52

android (abdominal) obesity

Answer 52

related to CVD, hypertension, and T2DM (increased health risk)