Energy Requirements and Balance

Question 1

What is a kilocalorie?

Answer 1

The amount of energy required to raise the temperature of 1 gram of water by 1 degree celsius.
1 kcal= 4.184 kJ and 1 kJ = .02389 kcal

Question 2

How is energy measured?

Answer 2

in units based on transfer of heat (calories) or in units based on performance of work (joules).

Question 3

Human energy expenditure consists of what 3 principles?

Answer 3

BEE (Basal energy expenditure), TEF (thermic effect of food), and EEPA (energy expenditure of physical activity)

Question 4

What is BEE?

Answer 4

the minimal energy expenditure required to support body functions in the absence of physical activity or food intake.

Question 5

What percentage of TEE does BEE account for?

Answer 5

50-70% of kcal/day.

Question 6

what is RMR?

Answer 6

The kcal your body burns while at rest.

Question 7

what is the kcal difference between BEE and RMR?

Answer 7

RMR is 10-20% higher than BEE because of the additional energy costs of arousal, posture, and being in a nonfasted state.

Question 8

What percentage of TEE does TEF account for?

Answer 8

5-15% (adults)

Question 9

What does direct calorimetry measure?

Answer 9

the transfer of heat from the body to the environment.

Question 10

how is direct calorimetry performed?

Answer 10

closed environmental chamber (bod pod).

Question 11

what does indirect calorimetry measure?

Answer 11

respiratory gas exchange; O2 uptake or CO2 release via the lungs is measured as a surrogate for heat production.

Question 12

what is a respiratory quotient?

Answer 12

the ratio of CO2 produced to O2 consumed, measured by indirect calorimetry, that provides information about whether fat or CHO is being used as fuel.

Question 13

what is PAL and how is it defined?

Answer 13

Physical Activity Level; defined as the ratio of TEE to BEE.

Question 14

How many kJoules are in 1 kcal?

Answer 14

4.184 kJ

1 kJ = .02389 kcal

Question 15

How quickly is liver glycogen stores depleted?

Answer 15

essentially depleted by a 24 hour fast.

Question 16

How quickly is muscle glycogen depleted?

Answer 16

can be largely exhausted in less than 1 hour during vigorous activity.

Question 17

What is the main function of stored glycogen?

Answer 17

1. to serve a source of glucose for output by the liver when plasma glucose levels decrease
2. to provide glucose 6-phosphate for use as fuel in skeletal muscle during exercise.

Question 18

Substantial net conversion of glucose, AA’s, or alcohol to fat will only occur if what is true?

Answer 18

if the intake of these macronutrients as well as total energy intake is quite high (excess of TEE).

Question 19

The body is considered to be made up of what six components?

Answer 19

lipid, water, PRO, osseous minerals, cell minerals, glycogen

Question 20

What % of the following makes up the body? 
lipids
water
PRO
minerals
CHO

Answer 20

14% lipids
62% water
17% PRO
6% minerals
1% CHO

Question 21

The most widely used assessments of body composition are what?

Answer 21

FM and FFM

Question 22

What is the difference between FFM and LBM?

Answer 22

FFM includes water, PRO, osseous and soft tissue minerals, and glycogen.
LBM includes the essential fat present in all nonadipose cells and tissues as well as the fat present in the central nervous system (CNS) and bone marrow.

Question 23

How much difference in % is there between FFM and LBM?

Answer 23

LBM is 2-3% greater than FFM in Men

LBM is 5-12% greater than FFM in Women

Question 24

What is currently considered the gold standard for assessing body composition?

Answer 24

DEXA (dual-energy x-ray absorptiometry)