Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

FNH 250 > Energy Balance & Weight Management > Flashcards

Energy Balance & Weight Management Flashcards

1
Q

What is a healthy body weight?

A

A healthy body weight is a weight…

  • at which you are at lowest risk for morbidity or mortality
  • that is easily achievable and sustainable
  • that is appropriate for your age and physical development
  • congruent with your family history and genetics
  • that promotes healthy lifestyle activities (e.g., healthy eating habits, regular physical activity, etc…)

Every individual has his or her own individual ‘healthy body weight’.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is BMI?

A
  • BMI = kg/m2
  • index of total body weight independent of height
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the advantages of BMI?

A
  • inexpensive
  • easy to calculate
  • quick estimate of relation to risk of disease (e.g., BMI >30 increased risk of T2D, hypertension, heart disease)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the disadvantages of BMI?

A
  • doesn’t indicate how much body weight is fat
  • doesn’t indicate location of body fat
  • only suitable for non-pregnant, non-lactating adults
  • should be used with other anthropometric assessments
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is any association between body weight and health determined?

A
  • no single measure should be used to assess body weight
  • several measures should be used to:
    • assess body composition
    • assess fat distribution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When focussing on nutritional assessment, data can be collected from which four different sources?

A

A, B, C, D:

  • Anthropometric – physical body
  • Biochemical – blood & tissue
  • Clinical – general appearance, blood pressure
  • Dietary – nutrients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is hydrodensitometry?

A

Underwater Weighing - measure of body fat composition

  • multiple submersions in tank of water
  • compare displacement of water with land weight to determine body volume and body density (weight/volume)
  • use Siri formula to accurately calculate % body fat within 2-3%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How can calipers be used to measure body fat percentage?

A
  • repeated measures taken at several sites:
    • subscapular (under shoulder blade)
    • suprailiac (between rib cage and hip bone)
    • triceps (back of upper arm)
    • thighs
  • measures are averaged and compared with standards
  • body fat estimate accurate within 3-4%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is bioelectrical impedance analysis?

A
  • measures resistance of tissue types to low grade electrical current passed through body under normal hydration status
  • fat tissue resists current more than lean tissue
  • accuracy within ~4%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is near infrared reactance?

A
  • wand strapped to bicep, scanner held in outreached hands
  • IR beam penetrates arm and is reflected back through the scanner to wand
  • measure change in IR level
  • fat tissue absorbs more light than lean tissue
  • low accuracy; not useful
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can isotope dilution be used for measuring body fat composition?

A
  • take baseline sample of salvia
  • drink measured amount of labelled water
  • wait specific amount of time then measure amount of label in second saliva sample
  • lean body mass (LBM) retains more label than fat tissue
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is Dual Energy X-Ray Absorptiometry?

A

DEXA SCAN!

  • measure the differential between two x-rays of separate energies
  • full body scan used to simultaneously measure different body tissues (bone, fat-free soft tissue, fat)
  • also used to measure specific tissues (e.g., bone density)
  • extremely accurate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the recommendations for waist circumference in Canada?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do the Canadian guidelines use both WC and BMI for recommendations of body composition?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Waist to Hip ratio and why is it useful?

A
  • provides an indication of where fat is located
    • Men waist:hip: <1.0 desirable
    • Women waist:hip: <0.80 desirable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the basic energy balance equation?

A

BMR: basal metabolic rate

PA: physical activity

TEF: thermic effect of food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a direct measurement of body expenditure?

A
  • direct measure of heat released from human enclosed in insulated metabolic chamber
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How many calories make up 1 lb of body fat?

A
  • 3500 kcal = ~0.45 kg (1 lb.) of body fat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How do we measure the energy in foods?

A
  • bomb calorimeter – direct measure of chemical energy in bonds in food that is released in the form of heat
  • use equations to determine relative efficiency of humans to extract energy when we “burn” foods
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do internal signals affect energy intake?

A
  • feeding and satiety are controlled by the brain
  • low blood glucose levels will trigger feeding
  • high blood glucose will trigger satiety
  • damage to the hypothalamus can result in over- eating (weight gain) or under-eating (weight loss)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the internal signal ‘hunger’.

A
  • inborn instinct
  • feeding centre in hypothalamus activated causing hormone release due to lack of nutrients in GI tract (e.g., ghrelin = hunger hormone)
  • contrasts to appetite – a learned behaviour – can interfere with hunger/satiety cycle
22
Q

Describe the internal signal ‘satiety’.

A
  • satiety centre in hypothalamus activated by presence of food in GI tract, distention, raised BGL, and hormonal signals (e.g., leptin = satiety hormone)
  • brain signals to stop eating
23
Q

How do external signals affect energy intake?

A
  • Environmental signals:
    • time of day
    • sight of food
    • smell of food
    • location (e.g., mall, cafeteria)…
  • Psychological signals:
    • many stimuli:
    • social influences, pressures, and situations
    • mood, stressful situations…
24
Q

What is an indirect measure of energy expenditure?

A
  • Respiratory Quotient (RQ) gas exchange (O2 consumed/CO2 exhaled) used to determine relative amount of energy needed to perform exercise or to determine BMR (~5 kcal/Ltr O2)
25
Q

What factors influence energy expenditure?

A
  1. Basal Metabolic Rate ~50-65%
  2. PhysicalActivity ~30-50%
  3. Thermic Effect of Food ~5-10%
26
Q

What is BMR?

A

Basal Metabolic Rate

  • ~50-65% of Energy-OUT
  • “organ metabolic rate”
  • respiration
  • circulation
  • core temperature
  • metabolism
  • minimum amount of energy needed at rest to sustain vital body functions
  • varies for each individual
27
Q

How is BMR measured?

A
  • measured under standard conditions
    • lying still
    • awake
    • 12-14 hour post-absorptive
    • thermal neutrality
28
Q

What factors influence BMR?

A

1. Age

  • highest at 1 year (per kg body weight)
  • adults: ~2% decrease per decade after 30 years

2. Growth

  • increased during childhood, adolescence, pregnancy

3. Size

  • height – tall, thin increased surface area, higher BMR
  • weight – energy expended for BMR is lower per kg at higher weights

4. Body composition

  • higher proportion of lean tissue increases BMR
  • males ~10% > than females
  • adult males: ~15% body weight as fat
  • adult females: ~25% body weight as fat

5. Physiological state (non-standard conditions)

  • fever increases BMR
  • hot and cold environments increases BMR
  • hyperthyroidism increases BMR
  • thyroid hormones can increase or decrease BMR
  • stimulant drugs: caffeine, tobacco increases BMR
  • luteal phase of menstrual cycle increases BMR
  • starvation/fasting/malnutrition decreases BMR
29
Q

How does physical activity affect ‘energy-out’?

A
  • ~30-50% of Energy-OUT
  • varies greatly from individual to individual
  • increased LBM raises BMR
  • impacted by FITT principle
    • Frequency
    • Intensity directly proportional to Energy-OUT
    • Time
    • Type – different effects
  • include endurance, flexibility & strength activities
30
Q

What are the health benefits of physical activity?

A
  • reduced risk for heart disease, stroke and hypertension
  • reduced risk for weight gain and obesity
  • reduced risk for type 2 diabetes
  • potential reduced risk for colon cancer
  • reduced risk for osteoporosis
  • improved sleep patterns
  • alleviate mental stress and depression
  • 20-30 min/day offers many health benefits
31
Q

Discuss the use of ATP and PCr during physical activity.

A
  • ATP used by all cells: limited supply in muscle cells (1-3 seconds)
  • PhosphoCreatine (PCr) in muscle splits and donates phosphate to regenerate ATP from ADP
  • combined, stores of ATP and PCr can fuel muscle cells working at maximal effort for about 3-10 seconds, then need to turn to CHO and FAT as fuel sources
32
Q

Discuss the use of carbohydrates during physical activity.

A
  • CHO (glucose) is a ready source of energy (from glycogen stores or blood) through Glycolysis – aerobic or anerobic
  • primary fuel source for quick, high intensity activities (e.g., sprinting, quick jumps)
33
Q

Discuss the use of FAT during physical activity.

A

FAT OXIDATION (Beta-oxidation)

  • fatty acids in triglycerides provide an abundant source of ATP under aerobic conditions only (no anerobic FA breakdown)
  • plenty of stored TG – even in lean people
  • TG supply >2X energy/gram compared with CHO
  • slower oxidation process for fat compared with CHO, fat doesn’t support quick, high intensity activities
34
Q

Compare the usage of fuels during different types of exercise.

A
35
Q

Discuss the use of PROTEIN during physical activity.

A
  • aerobic breakdown
  • amino acids not used much to support cellular ATP needs for activities (account for ~3-6% of energy need)
  • important non-protein function of glucogenic amino acids is their conversion to GLU (gluconeogenesis) to raise BGL during activity
  • amino acids used to build and repair lean tissue after activity
  • PRO needs of athletes only slightly higher than needs of non-athletes
36
Q

Dicuss where & how much energy is stored for physical use in the body.

A
  • most energy storage in body in adipose tissue as TG
  • females ~25% body mass as fat
  • 55 kg female ~14 kg fat mass = 14,000 g fat
  • 14,000 g X 9 kcal/g ~126,000 kcal of stored energy as TG
  • males ~15% body mass as fat
  • 70kg male~10kgfatmass=10,000gfat
  • 10,000 g X 9 kcal/g ~90,000 kcal of stored energy as TG
  • smaller amount of E storage in liver and muscle as glycogen
  • about 400 kcal of CHO stored as glycogen in liver and 1000- 1500 kcal of CHO stored as glycogen in muscle, dependent upon training
37
Q

When is there anaerobic breakdown of CHO?

A
  • Split-second surges of power as in the heave of a barbell or jump of a basketball player involve anaerobic breakdown of CHO.
38
Q

Where does abundant energy come from?

A
  • Abundant energy from the breakdown of fat comes only from aerobic metabolism.
39
Q

What energy does low intensity long duration activities use?

A
  • Low- to moderate-intensity aerobic exercises that can be sustained for a time (more than 20 minutes) use limited glucose and more fat for fuel.
40
Q

Summarize using nutrients for energy.

A
  • GLU:Aerobic and anerobic breakdown
  • Fattyacids, Aminoacids: Only aerobic breakdown
  • Glucose and fatty acids primarily used for energy; amino acids to a much lesser extent
  • Glucose can be synthesized from all carbohydrates, most amino acids, the glycerol portion of TG & ethanol
  • All energy-yielding nutrients consumed in excess can contribute to fat storage
  • Water: necessary for catabolic reactions; keep well hydrated at all times
41
Q

Discuss the importance of water regarding physical activity.

A
  • An appropriate intake of macronutrients, micronutrients and water all support physical activity.
  • To prevent dehydration and the fatigue that accompanies it, drink plenty of liquids before, during, and after physical activity.
42
Q

What is TEF?

A
  • Thermic Effect of Food
  • ~5-10% of Energy-OUT
  • energy used by body to process food consumed
  • peristalsis, segmentation, muscle action
  • production of digestive juices
  • active transport absorption of some nutrients § transport, metabolism, storage of nutrients
  • TEF is proportional to kcal consumed
43
Q

What are minor terms usually excluded from the energy balance equation?

A
  • temporary starvation
  • extreme cold temperature
  • altitude ~3000m
  • trauma
44
Q

Discuss dietary changes that can be made to acheive weightloss.

A
  • choose smaller portions of lower-fat foods more often
  • make nutrient-dense food choices
  • avoid fad diets and “quick fix” herbal or other remedies marketed for weight loss – adequacy, balance, kcalorie control, moderation, and variety are key principles to follow
  • don’t drop kcalorie intake below ~1500-1800 kcal/day – otherwise food selections become restricted and if drop <~1200 kcal/day, body slows metabolism to conserve energy
45
Q

Discuss physical activity as a weightloss strategy.

A
  • enjoy different types of physical activity every day
  • initially aim for 30 minutes of activity each day
  • once aerobic capacity increased, maintain an accumulated total of 150 minutes per week (minimum 10 minute intervals) of moderate-to-vigorous aerobic physical activity
46
Q

Discuss behavioural changes as a weight loss strategy.

A
  • remove tempting energy-dense foods from your regular daily habits (e.g., avoid walking by the bakery or fast food outlets, don’t shop when hungry)
  • use smaller dishes and consume smaller portions
  • learn which foods are high kcalorie (e.g., in restaurants, at take-out establishments) and avoid consuming them on a regular basis
  • turn off the TV when eating and take time to enjoy your food
  • don’t be harsh with yourself if you fail to meet your plan, but don’t give up – rethink things through, make a new and realistic plan, and try again
47
Q

Discuss dietary changes as a weight gain strategy.

A
  • consume ~500-700 kcal/d greater than EOUT
  • expect to feel full
  • don’t forget to eat – meals and snacks throughout the day
  • try to eat a little more at each meal and/or snack
  • pack healthy snacks with you throughout the day
  • use larger bowls, plates, cups
  • eat granola, nuts, dried fruit at end of meal
  • drink healthy energy-dense beverages
  • use oil in casseroles, soups, on salads

§ try a muffin instead of bread

48
Q

Discuss physical activity as a weight gain strategy.

A
  • enjoy different types of physical activity
  • aim for at least 30 minutes of moderately-intense activity 5x per week
  • activity can stimulate appetite
49
Q

Discuss behavioural changes as a weight gain strategy.

A
  • set aside times in your day to eat
  • learn which nutrient-dense foods are higher in kcalorie – include in your diet on a regular basis
  • have foods around you – in your backpack, on the kitchen counter, etc.
50
Q

Discuss health issues associated with energy imbalance.

A
51
Q

What are the functions and sources of energy?

A

Functions

  1. Maintaining basal body metabolism
  2. Performing work
  3. Processing food consumed

Sources

  • foods and beverages consumed (except water)
52
Q

Discuss EER.

A
  • Goal: energy intake that maintains or attains a healthy body weight
  • Balance Energy-IN with Energy-OUT to maintain a healthy body weight over time
  • monitoring own body weight is best indicator of energy balance; keep well hydrated

FNH 250 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions