Unit 7 - Energy Metabolism Flashcards
(30 cards)
Where is net energy stored?
Adipose tissue
What is alcohol stored as?
Fat and slows metabolism of fat
What are the 3 components of energy expenditure?
- Basal metabolism
- Voluntary activities
- Thermic effect of food
What does Basal metabolism do?
Everything the body does outside of awareness
BMR - 12-16 hrs after fasting/sleeping (increased with strength exercise)
RMR - little higher
What component of energy expenditure has the largest expenditure from food?
Basal metabolism
What factors are included in Voluntary activities as a component of energy expenditure ?
muscle mass
body weight
activity
What is the thermic effect of food?
cell actvity to move food and produce gastric/other juices creates heat
How much % of total food energy taken in is spent in the thermic effect?
10%
Which of the 3 components of energy expenditure has the greatest variability?
Voluntary activities
What factors affect basal metabolic rate?
age - BMR slows because lean body mass diminishes
height - tall, thin peeps, higher BMR
growth - kids, teens, pregnant people higher BMR
body composition (sex) - lean tissue=higher BMR
fever - raises BMR
stresses - disease and drugs - raise BMR
environment temps - heat and cold raise BMR
fasting/starvation -lowers BMR
malnutrition - lowers BMR
hormones - speed up or slow down depending
smoking -nicotine increases energy expenditure
caffeine- increases energy expenditure
sleep - BMR is lowest
What are the 5 factors that energy requirement calculations should take into account?
- Sex - body composition
- Growth - BMR higher during growth periods
- Age- energy requirements decrease with age
- Physical activity
- Height & weight - taller/heavier use more energy
BMI calculation
BMI = weight in kg / (height in m)2
BMI classification
Underweight BMI: <18.5
Normal BMI: 18.5-24.9
Overweight BMI: 25-29.9
Obese (class I) BMI: 30- 34.9
Obese (class II) BMI: 35-39.9
Extreme Obesity (class III) BMI: >40
What are the limitations of BMI?
Not helpful for athletes with lots of muscle mass
not helpful for older adults 65+
not for pregnant/lactating people
Does not account for whether the weight is fat or muscle
what are the 3 methods for assessing body weight and composition?
*Anthropometry
1. Central obesity
2. Waist circumference
3. Skin fold measures
What is Prader-Willi syndrome?
- genetic disorder
- excessive appetite
- massive obesity
- short
- often intellectual DA
How many sites in human genome associated with obesity and fat distribution?
Over 300
What does it mean if someone has high LPL?
Lipoprotein lipase
- very efficient at storing fat in fat cells
- muscle cell storage is normal levels
What is Leptin?
Feedback mechanism
- obesity gene
- hormone produced and secreted by fat cells
- stimulated to suppress appetite and increase energy expenditure
- suppression of leptin means increase appetite and decrease energy expenditure
What is Ghrelin ?
appetite stimulating hormone that is made and secreted by stomach cells. It works in the hypothalamus to promote efficient energy storage
Healthy waist circumference for male & female?
male - <40 inches
female - <35 inches
What are the 3 theories that can account for development of obesity
- Fat Cell Development: The theory that body fatness is determined by the number and size of fat cells
- Set-point Theory: The theory that the body tends to maintain a certain weight by means of its own internal controls.
- Intestinal Bacteria: The makeup of the intestinal microbiota can change when body weight changes, as the microbiota may influence energy balance.
What is the difference between hunger and appetite?
Hunger is natural
Appetite is learned
What is the different between satiation and satiety?
Satiation tells us to stop eating and builds through the meal
Satiety reminds us not to start eating again- after we have eaten