chapter 10 - energy balance & body composition

Question 1

energy balance

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

energy intake components

Answer 4

any foods that has calories: carbs, protein, fat, alcohol

Question 5

energy expenditure components

Answer 5

1. basal metabolism
2. thermic effect of food (TEF)
3. physical activity
4. thermogenesis

Question 6

thermogenesis

Answer 6

minor form of energy output (shivering, fidgeting)

Question 7

BMR

Answer 7

basal metabolic rate = minimum amount of energy required for body functions when you’re resting

this is the LARGEST component of energy expenditure (60-70%)

Question 8

increase BMR

Answer 8

• muscle mass
• body temp
• stress hormones
• thyroid hormones
• caffeine, tobacco
• recent exercise

Question 9

decrease BMR

Answer 9

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

Question 10

RMR

Answer 10

resting metabolic rate: used if a person isn’t fasting or rested

about 6% higher than the BMR

Question 11

BMR & RMR units

Answer 11

number of calories burned per hour

women = 0.9 calories/kg per hour
men = 1.0 calories/kg per hour

Question 12

factors influencing body weight & composition

Answer 12

genetics & environment

Question 13

physical activity and energy expenditure

Answer 13

most variable component of energy expenditure

increases kcal needs by about 25-40% (can be higher/lower)

Question 14

TEF

Answer 14

thermic effect of food (digestion, absorption, metabolism) accounts for 5-10% of kcal

highest for protein

influenced by food composition & meal size

Question 15

direct calorimetry

Answer 15

estimates energy expenditure by measuring amount of heat released by body

idea = similar to bomb calorimeter (where they burn food) but this time a PERSON’S heat release is measured by putting them in a chamber surrounded by water

expensive, complicated, not often used

Question 16

adaptive thermogenesis

Answer 16

contributes a SMALL amount to expenditure

triggered by cold, overfeeding, trauma, starvation

Question 17

indirect calorimetry

Answer 17

collects air expired during a certain time period

considers amount of oxygen consumer and CO2 products

doubly-labeled water also used

Question 18

EER

Answer 18

Estimated Energy Requirements = equations based on evidence gathered thru direct & indirect calorimetry

Question 19

EER factors

Answer 19

energy needs are based on:
- weight
- height
- sex
- age
- activity level

Question 20

hunger

Answer 20

physiological drive to find/eat food

controlled by organs, hormones, & nervous system

Question 21

appetite

Answer 21

psychological drive to eat

impacted by EXTERNAL factors

Question 22

satiety

Answer 22

feeling of fullness following consumption of food

regulated by hypothalamus

Question 23

satiation

Answer 23

causes us to stop eating

happens because of secretion of hormones during digestion

promoted by:
- sensory aspects of food
- knowledge food has been consumed
- chewing
- expansion of stomach & intestines
- effects of digestion, absorption, metabolism
- decrease in ghrelin

Question 24

ghrelin

Answer 24

hormone that acts in the hypothalamus

promotes food intake: increases appetite, smell sensitivity, energy storage

Question 25

leptin

Answer 25

hormone that acts in the hypothalamus signals brain to decrease food intake rises when body fat increases (secreted by adipose tissue

Question 26

long-term satiety

Answer 26

promoted by body composition (amount of body fat)

Question 27

satiety process

Answer 27

hours after eating, macro levels in the blood begin to fall - body begins to use stored energy - satiety signals diminish - cortisol & ghrelin stimulate appetite

Question 28

assess weight status

Answer 28

current recommendations say to evaluate: - total body fat - location of body fat - weight-related medical complications

Question 29

BMI

Answer 29

Body Mass Index, preferred height-to-weight standard

Question 30

BMI benefits

Answer 30

- linked to longevity - easy to assess - applies to men & women - accurate for MOST people

Question 31

BMI exceptions

Answer 31

not appropriate for: - children - teens - older adults - pregnant/lactating women - people under 5' - muscular people

Question 32

body composition methods

Answer 32

1. underwater weighing 2. air displacement 3. skinfold thickness 4. bioelectrical impedance (electrical current sent through body) 5. dual energy x-ray absorptiometry (DXA) = MOST accurate

Question 33

body fat levels

Answer 33

men: 8-24% women: 21-35%

Question 34

healthy weight

Answer 34

body weight that doesn't increase risk of weight-related health problems or diseases

Question 35

realistic healthy weight

Answer 35

a RANGE: depends on gender, height, muscle mass achieved & sustained without restriction

Question 36

android obesity

Answer 36

abdominal obesity = large waist circumference associated with increased health risk

Question 37

android obesity risk factors

Answer 37

- male - high glycemic diets - high alcohol consumption - smokers

Question 38

android obesity diseases

Answer 38

increased risk of: - CVD - hypertension -T2DM