Exam 4 Energy Balance

Question 1

What does a bomb calorimeter measure

Answer 1

Used to measure the calorie value in foods

Question 2

List physiological fuel values for carbohydrate, protein, fat and alcohol? Why are these values typically lower than values derived from a bomb calorimeter

Answer 2

Carbs: 4g/kcal Protein: 4g/kcal Fat: 9kcal/g Alcohol: 7kcal/g
Protein example: things like the amine in the amino acid don’t get broken down all the way and the nitrogen gets converted into urea and excreted in the urine

Question 3

The heat of combustion in a bomb calorimeter for protein is 5.6 kcal/g, yet on a food label it tells me that protein has 4 kcal/g. Why are these values different

Answer 3

The amount listed on a food label is the amount that is possible for the body to process. Our bodies aren’t as efficient as a machine which can process the full amount of calories in the food

Question 4

Describe indirect calorimetry in measuring energy expenditure in humans

Answer 4

Measures respiratory gas exchange from which energy expenditure can be estimated. O2 consumption and CO2 production occur during the oxidation of carbs, protein and fat. Heat production can then be calculated from this measurement

Question 5

List the three categories of energy expenditure

Answer 5

BMR,PA and thermic effect of food

Question 6

BMR

Answer 6

Energy needed to maintain your metabolism needed for life. 60-65%

Question 7

PA

Answer 7

Energy used for all muscular work 25-35%

Question 8

Thermic effect of food

Answer 8

Energy to process food 5-10%

Question 9

What factors or characteristics can raise or lower basal metabolic rate (BMR)/resting energy expenditure (REE)

Answer 9

Increases with increasing body weight and effect by composition (takes more energy to maintain lean tissue) Also higher in men than women and can decrease with age

Question 10

When you eat much fewer kcal than usual for a few days (say, cut in half), what may happen to your BMR/REE

Answer 10

Your BMR will decrease because it will lower the amount of energy that is needed to maintain body weight

Question 11

What range of physical activity level (PAL) is associated with decreased risk of CVD

Answer 11

1.6-1.9

Question 12

If Sonia’s ate approximately the same amount of kcalories from fish (high protein), olive oil (high fat) and rice (high carbohydrate), which would have the highest thermic effect of food?

Answer 12

Carbs and protein

Question 13

“Easy to Use” formula for calculating REE/BMR

Answer 13

Females: (Weight (kg) X 0.9) 24
Males: weight (kg) X 24