Energy expenditure week 6

Question 1

What are the 3 indirect v0s measurements?

Answer 1

1.Douglas bag technique
* Meteorological balloons
* Old, but accurate and reliable
backup and gold standard

2. Portable spirometry
3. Computerized instrument

Question 2

Purpose of Indirect calorimetry?

Answer 2

Estimates rate of energy use
* Measurement of steady-state oxygen
consumption (VO2)
* 1 L O2 ~ 5 kcal

Question 3

what is V02 measured in?

Answer 3

1L o2 =5 kcal

Question 4

what is the Caloric equivalent to of o2 uptake v02?

Answer 4

kcal/L of o2

Question 5

what are the Kcal/L of o2 for
fats
carbs
proteins

Answer 5

Fat=9.0 kcal/g
CHO 4.0 kcal/g
Protein = 4.0 kcal/g

• 1 L of O2 yields:
  – 5.05 kcal CHO, 4.68 kcal fats
  ∙

Question 6

Respiratory exchange ratio? define it

Answer 6

The respiratory exchange ratio is the ratio between the metabolic production of carbon dioxide and the uptake of oxygen. The ratio is determined by comparing exhaled gases to room air.

Question 7

equation ?

Answer 7

Respiratory exchange ratio (RER) describes this ratio
of metabolic gas exchange
RER = CO2 produced / O2 consumed
* Provides a convenient guide to approximate nutrient
mixture catabolized for energy
* Seldom reflects oxidation of one macronutrient, but instead mixture with an RQ intermediate between 0.70 and 1.00
* CHO: RER = 1.00
* Protein: RER = 0.82
* Fat: RER = 0.70
Respiratory exchange ratio

Question 8

what is resting metabolic/basal rate/

Answer 8

sum of metabolic processes required to sustain
normal regulatory balance and body functions
during the resting state
* Oxygen consumption values for RMR range
between 160 and 290 mL/min (0.8 to 1.43
kcal/min)
* 3.5 ml/kg/min
* 1 MET
Also approximates the kcal burned per kg per

Question 9

what influences M rate?

Answer 9

• Influences: body size, health/ fitness, muscle
  mass, age, hormones, body temperature

Question 10

what is Metabolic at rest measured in? it is relative to body mass

Answer 10

Mets =metabolic equivalent at rest
3.5ml/kg/min

Question 11

how can it be use in exercise?

Answer 11

Exercise intensity expressed as
multiples of the MET e.g
exercise can be used to establish how much above resting your at

Question 12

Approximates the kcal burned per kg per
hour (kcal∙kg-1∙hr-1)
if exercising Mets is 10.2 MET?

relative ?

Answer 12

• 10.2 MET x 3.5 = 35.7 ml∙kg-1∙min-1
• 35.7 ml∙kg-1∙min-1 x 60 min∙hr-1
  = 2142 ml∙kg-1∙hr-1
• 2.14 L∙kg-1∙hr-1 x 5 kcal∙L-1
  = 10.7 kcal∙kg-1∙hr-1
  Just multiply by weight

Question 13

EE values/units

Answer 13

VO2 – volume of oxygen consumed (L/min)
VCO2 – volume of carbon dioxide produced (L/min)
VE – expired air volume per minute (L/min)
%FEO2 – fractional concentration of O2 in expired air
%FECO2 – fractional concentration of CO2 in expired air
ATPS – Ambient Temperature Pressure Saturated
STPD – Standard Temperature Pressure Dry Factor