Chapter 3: Energy Systems and Exercise

Question 1

Creatine phosphate (CrP)

Answer 1

organic compound that stores potential energy in its phosphate bonds, stored in muscles and other tissues

Question 2

Characteristics of creatine phosphate system (ATP-PC)

Answer 2

• one chemical step
• catalyzed by creatine kinase
• very fast reaction
• one ATP per CrP molecule
• 5-10 second duration
• Anaerobic
• Fatigue associated with CrP depletion
• Predominant energy system in very high intensity exercise, ‘power’ events

Question 3

Creatine

Answer 3

• consumed in the diet and synthesized by amino acids
• sources in diet fish and beef
• 1/3 stored in muscle. 2/3 as creatine phosphate
• excretion is approximately 2/g per day
• vegetarians have less in muscle in than meat eaters

Question 4

Characteristics of anaerobic glycolysis

Answer 4

• 18 chemical steps/reactions, 6 are repeated
• 12 chemical compounds, 11 enzymes
• rate-limiting enzyme, phosphofructokinase (PFK)
• fast but not as fast as ATP-PC
• Two ATP produced via glucose, 3 ATP produced via glycogen
• Anerobic
• 1-2 minute duration
• fatigue associated with decreased PH
• sustained repeated sprints, 400 m sprint

Question 5

Glycogenolysis

Answer 5

metabolic breakdown of glycogen

Question 6

glycolysis

Answer 6

metabolic breakdown of glucose

Question 7

Metabolic acidosis

Answer 7

Decrease in PH associated with high intensity exercise and the use of the anerobic glycolysis energy system

Question 8

Lactate

Answer 8

the metabolic end product of glycolysis

• lactate is metabolized aerobically
• converted to pyruvate
• in the liver, converted to glucose by the cori cycle

Question 9

Pyruvate

Answer 9

chemical compound that is an important intermediate of glycolysis

Question 10

Rate-limiting enzyme

Answer 10

in a series of chemical reactions, the enzyme that influences the rate of the entire series of reactions by changes in its activity

Question 11

Lactate Threshold

Answer 11

• Point of sudden increase in blood lactate concentration
  • Mistakenly called Anaerobic Threshold(AT)
  • Lactate production outpaces lactate removal mechanisms

Question 12

oxidative phosphorylation

Answer 12

the aerobic energy system

Question 13

1st phase of oxidate phosphorylation

Answer 13

takes place in the mitochondria, carbs, fats, and proteins are prepared to be metabolized aerobically

Question 14

Krebs cycle

Answer 14

series of oxidation-reduction reactions used to metabolize carbohydrates, fats, and proteins

Question 15

electron transport phase

Answer 15

a series of electron-passing reactions that provides energy for ATP formation

Question 16

Characteristics of oxidative phosphorylation

Answer 16

• 124 chemical steps/reactions
• 30 compounds, 27 enzymes
• rate-limiting enzymes: PFK, IDH, COX
• slow
• 30 ATP via glucose, 31 via glycogen
• potentially limitless duration
• aerobic
• fatigue associated with fuel depletion
• predominant energy system in endurance exercise

Question 17

oxidation

Answer 17

giving up electrons

Question 18

reduction

Answer 18

accepting electrons

Question 19

Creatine supplementation

Answer 19

allows strength and power athletes to sustain high-intesnsity training

Question 20

the preferred energy source by exercising muscle for the process of aerobic glycolysis

Answer 20

glycogen

Question 21

how does the amount of ATP produced from the breakdown of one molecule of carbohydrate compare to the breakdown of one molecule of a fatty acid

Answer 21

the amount by fat is about 3.5 times greater

Question 22

respiratory exchange ratio (RER)

Answer 22

ratio of carbon dioxide production to oxygen consumption; used to determine percentage of fats and carbs used for metabolism

Question 23

beta-oxidation

Answer 23

chemical process of breaking down fatty acid chains for aerobic metabolism

Question 24

fed-fast state

Answer 24

depends on the utilization of substrates, influences metaabolism

Question 25

oxygen deficit

Answer 25

the lag in oxygen consumption at the onset of exercise

Question 26

oxygen debt or excess post exercise oxygen consumption

Answer 26

the elevated oxygen consumption that occurs for a short time during the recovery period after an exercise bout has ended

Question 27

average oxygen consumption

Answer 27

3.5 ml/kg/min

Question 28

fuel utilization of carbs

Answer 28

metabolized in oxidative phosphorylation (glucose or glycogen)

Question 29

fuel utilization of fats

Answer 29

metabolized aerobically by the oxidation of fatty acids

Question 30

fuel utilization of proteins

Answer 30

metabolized aerobically by the oxidation of amino acids

Question 31

lypolysis

Answer 31

term used for the breakdown of triglycerides