lecture 16

Question 1

how much protein should you consume before weight lifiting

Answer 1

3-60min prior

- provide building blocks for protein sythesis

Question 2

The role of protein in the body

Answer 2

• tissue structure
• transport
• muscle contraction
• hormonal systems
• metabolic regualtion

Question 3

purpose of protein metabolism

Answer 3

• supply amino acids for various metabolic anabolic building procces in the body
• amino acids = building blocks
• protein can also be catabolised for energy

Question 4

steps of catabolism

Answer 4

1- During catabolism (breakdown), protein first degrades into its component amino acids
2- The amino acid molecule then loses its nitrogen (amino) group in a process called deamination
3- The amine group is then excreted from the body as urea.

Question 5

metabolism

Answer 5

The sum of all chemical reactions occurring in the body.

Question 6

3 major purposes that are related to matabolism

Answer 6

1. Basal Metabolic Rate (BMR) = Min amount energy to sustain bodies vital function
2. Thermic effect of food consumed. Body needs energy to digest food
3. Physical activity

Question 7

what can metabolism tell you?

Answer 7

1. What % of CHO + lipids are being metabolised for fuel during rest & exercise.
2. How many calories are being burned at rest and during exercise
   - assists in diet & exercise intervention

Question 8

how can you determine your metabolism

Answer 8

• rate of heat production

measurement of heat production = direct calorimetry

Question 9

direct calorimetry

Answer 9

Direct calorimetry uses a human calorimeter chamber.
Circulating water absorbs heat of subject.
- costly

Question 10

indirect calorimetry

Answer 10

Measurement of O2 uptake = indirect estimate of energy expenditure

Oxygen uptake = difference between O2 inspired and volume O2 expired

Question 11

Why do you think that females have a lower metabolism than males??

Answer 11

Males have more muscle mass than females which increases the metabolic rate
- Females have more fat which is less reactive

Question 12

The Respiratory Exchange Ratio helps

Answer 12

1- determine the food mix being burned,
2- the caloric value of this food.
CO2 produced/O2 consumed

Question 13

how does RER work

Answer 13

• During steady state exercise and rest , oxygen is used to break CHO and lipids down in order to produce energy
• CHO and lipids have different chemical structures
• CHO & Lipids require different amounts of oxygen to break them down so to be used as a fuel.
  consequently:
• different amounts of CO2 will be produced for CHO versus lipid molecules

Question 14

oxidation of CHO

Answer 14

• 6 molecules are needed to breakdown 1 molecule of glucose - C6H12O6 + 6 O2
• broken down into: 6CO2 + 6H2O + energy
• RER = CO2/O2
  CHO = 6/6 = 1.0
• check caloric tables to see how much energy is used

Question 15

oxidation of lipids

Answer 15

• 23 oxygen molecules are needed to breakdown one lipid molecule - C16H32O2 + 23O2 this will result = 16CO2 + 16H20 + energy
  calc RER CO2/O2 = 0.7