Metabolic Responses to Exercise: Learn and Test Your Knowledge

Question 1

Which of the following is NOT a macronutrient used for energy production?

Accepted Answer

Vitamins

Answer

Carbohydrates

Answer

Fats

Answer

Proteins

Question 2

During high-intensity exercise, which metabolic pathway is primarily responsible for generating ATP?

Accepted Answer

Glycolysis

Answer

Citric acid cycle

Answer

Oxidative phosphorylation

Answer

Beta-oxidation

Question 3

What is the primary role of the lactate shuttle system?

Accepted Answer

To transport lactate from muscles to the liver

Answer

To convert lactate to pyruvate within mitochondria

Answer

To regulate blood pH

Answer

To enhance glucose availability for muscles

Question 4

Which buffer system is primarily responsible for maintaining blood pH during exercise?

Accepted Answer

Bicarbonate buffer system

Answer

Phosphate buffer system

Answer

Protein buffer system

Answer

Hemoglobin buffer system

Question 5

Which of the following is not a potential consequence of prolonged exercise?

Accepted Answer

Increased glycogen storage

Answer

Dehydration

Answer

Muscle damage

Answer

Reduced immune function

Question 6

Which factor primarily contributes to the acidic shift in the body's pH balance during exercise?

Accepted Answer

Increased lactate production

Answer

Increased bicarbonate production

Answer

Increased carbon dioxide production

Answer

Increased oxygen consumption

Question 7

In response to exercise-induced hydrogen ion accumulation, the body primarily employs which mechanism for buffering?

Accepted Answer

Bicarbonate buffering

Answer

Phosphate buffering

Answer

Protein buffering

Answer

Respiratory compensation

Question 8

Catalyzing the conversion of pyruvate to lactate, which enzyme plays a key role in anaerobic metabolism?

Accepted Answer

Lactate dehydrogenase

Answer

Pyruvate dehydrogenase

Answer

Creatine kinase

Answer

Adenylate kinase

Question 9

What is the primary purpose of the Cori cycle?

Accepted Answer

Transporting lactate from muscles to the liver for conversion back to glucose

Answer

Regenerating ATP from ADP

Answer

Producing pyruvate from lactate

Answer

Removing carbon dioxide from the blood

Question 10

During exercise, which mechanism primarily accounts for the increase in heart rate?

Accepted Answer

Increased sympathetic nervous system activity

Answer

Increased parasympathetic nervous system activity

Answer

Increased blood pressure

Answer

Increased stroke volume

Question 11

Which of the following is NOT a potential contributor to exercise-induced muscle damage?

Accepted Answer

Adequate warm-up prior to exercise

Answer

Eccentric muscle contractions

Answer

Prolonged exercise duration

Answer

High-intensity exercise

Question 12

In response to repeated endurance exercise, which adaptation is primarily observed?

Accepted Answer

Increased mitochondrial density

Answer

Increased muscle mass

Answer

Improved buffering capacity

Answer

Enhanced neural efficiency

Question 13

Which of the following is the primary substrate utilized for energy production during high-intensity exercise of 10-90 seconds?

Accepted Answer

Glycogen

Answer

Fat

Answer

Protein

Answer

Ketones

Question 14

What is the principal end product of anaerobic glycolysis, a process that occurs when exercise intensity exceeds aerobic capacity?

Accepted Answer

Lactate

Answer

Pyruvate

Answer

Citrate

Answer

Acetyl-CoA

Question 15

What is the primary role of bicarbonate in maintaining acid-base balance during exercise?

Accepted Answer

Buffer against hydrogen ions

Answer

Convert lactate to pyruvate

Answer

Promote oxygen delivery

Answer

Stimulate gluconeogenesis

Question 16

Which of the following exercises would likely elicit the greatest increase in lactate production?

Accepted Answer

Running at 90% of VO2max for 5 minutes

Answer

Cycling at 70% of VO2max for 30 minutes

Answer

Weightlifting with heavy weights for 10 repetitions

Answer

Swimming at a moderate pace for 1 hour

Question 17

What is the significance of the respiratory compensation point during exercise?

Accepted Answer

The point at which lactate production equals lactate removal

Answer

The point at which exercise intensity exceeds the anaerobic threshold

Answer

The point at which ventilation increases significantly

Answer

The point at which heart rate reaches its maximum

Question 18

Which hormone is primarily responsible for promoting gluconeogenesis, the process of converting non-carbohydrate substrates into glucose, in response to increased exercise intensity?

Accepted Answer

Glucagon

Answer

Insulin

Answer

Epinephrine

Answer

Testosterone

Question 19

Which dietary supplement has been suggested to improve lactate tolerance, allowing individuals to perform better during high-intensity exercise?

Accepted Answer

Sodium bicarbonate

Answer

Creatine

Answer

Caffeine

Answer

Branched-chain amino acids

Question 20

Which of the following is **NOT** a major substrate used during exercise?

Accepted Answer

Creatine

Answer

Glucose

Answer

Fat

Answer

Protein

Question 21

What is the primary product of anaerobic glycolysis?

Accepted Answer

Lactate

Answer

Pyruvate

Answer

Acetyl-CoA

Answer

ATP

Question 22

Which of the following buffers helps to neutralize lactic acid produced during exercise?

Accepted Answer

Bicarbonate

Answer

Phosphate

Answer

Protein

Answer

Hemoglobin

Question 23

What is the primary energy source for **low-intensity** exercise lasting up to 30 seconds?

Accepted Answer

ATP-PC system

Answer

Glycolysis

Answer

Oxidative phosphorylation

Answer

Ketone bodies

Question 24

What is the primary mechanism for replenishing muscle glycogen stores after exercise?

Accepted Answer

Glycogenesis

Answer

Glycogenolysis

Answer

Gluconeogenesis

Answer

Lipogenesis

Question 25

What is the primary role of creatine phosphate during exercise?

Accepted Answer

To provide a rapid source of ATP

Answer

To buffer lactic acid

Answer

To transport oxygen to the muscles

Answer

To stimulate glycogen breakdown

Question 26

During very short-duration, high-intensity exercise (less than 10 seconds), which substrate is primarily used to produce ATP?

Accepted Answer

Creatine phosphate

Answer

Glycogen

Answer

Fatty acids

Answer

Glucose

Question 27

What is the primary mechanism for buffering hydrogen ions during exercise?

Accepted Answer

Bicarbonate buffering

Answer

Phosphate buffering

Answer

Protein buffering

Answer

Hemoglobin buffering

Question 28

How does the body prioritize fuel utilization during exercise?

Accepted Answer

Carbohydrate-dominant initially, transitioning to fat utilization later

Answer

Fat-dominant initially, transitioning to carbohydrate utilization later

Answer

Equal reliance on carbohydrates and fats throughout exercise

Answer

Prioritization is based on substrate availability

Question 29

What is the significance of the anaerobic threshold in exercise performance?

Accepted Answer

It indicates the point where lactate production exceeds removal

Answer

It represents the onset of fatigue

Answer

It is the highest intensity at which steady-state exercise can be maintained

Answer

It is unrelated to exercise performance

Question 30

Which of the following is NOT a usable substrate for energy production during exercise?

Accepted Answer

Carbon dioxide

Answer

Glucose

Answer

Fat

Answer

Protein

Question 31

What is the primary end product of anaerobic glycolysis?

Accepted Answer

Lactate

Answer

Pyruvate

Answer

Acetyl-CoA

Answer

NADH

Question 32

Which of the following factors primarily influences lactate production during exercise?

Accepted Answer

Exercise intensity

Answer

Muscle glycogen stores

Answer

Blood pH

Answer

Muscle temperature

Question 33

What is the primary role of bicarbonate in acid-base balance during exercise?

Accepted Answer

Buffering hydrogen ions

Answer

Producing hydrogen ions

Answer

Releasing carbon dioxide

Answer

Increasing blood pH

Question 34

What is the main function of the Cori cycle?

Accepted Answer

To convert lactate to glucose in the liver

Answer

To convert glucose to lactate in the muscles

Answer

To regulate blood sugar levels

Answer

To produce ATP

Question 35

What is the primary role of the enzyme pyruvate dehydrogenase in carbohydrate metabolism?

Accepted Answer

To convert pyruvate to acetyl-CoA

Answer

To convert acetyl-CoA to pyruvate

Answer

To produce lactate from pyruvate

Answer

To consume oxygen

Question 36

What is the primary end product of glycolysis under anaerobic conditions?

Accepted Answer

Lactic acid

Answer

Acetyl CoA

Answer

Ethanol

Answer

Pyruvic acid

Question 37

Which buffer system is primarily responsible for counteracting the metabolic acidosis caused by lactate accumulation during intense exercise?

Accepted Answer

Bicarbonate buffer system

Answer

Creatine phosphate buffer system

Answer

Protein buffer system

Answer

Phosphate buffer system

Question 38

What is the primary function of the Cori cycle?

Accepted Answer

To convert lactate produced in the muscles back to glucose in the liver and muscle

Answer

To produce energy through aerobic respiration

Answer

To convert glucose into glycogen in the muscles

Question 39

Which type of muscle fiber is predominantly responsible for providing energy during prolonged, low-intensity exercise?

Accepted Answer

Type I slow-twitch

Answer

Type IIa fast-twitch

Answer

Type IIx fast-twitch

Question 40

The Cori cycle involves the:

Accepted Answer

Conversion of lactate to glucose in the liver

Answer

Synthesis of protein during recovery

Answer

Breakdown of glucose in muscle cells

Answer

Oxidation of fat for energy production

Question 41

Which of the following factors influences the rate of substrate utilization during exercise?

Accepted Answer

Intensity and duration of exercise

Answer

Ambient air temperature

Answer

Athlete's shoe size

Answer

Color of the training facility

Question 42

How does the body maintain acid-base balance during exercise?

Accepted Answer

Through buffering systems and increased ventilation

Answer

Lowering body temperature

Answer

Decreasing blood volume

Question 43

The term 'oxygen debt' refers to:

Accepted Answer

The additional oxygen consumed after exercise to restore homeostasis

Answer

The amount of oxygen required for muscle contraction

Answer

The oxygen deficit during the initial stages of exercise

Question 44

Which of the following statements about the relationship between exercise intensity and substrate utilization is accurate?

Accepted Answer

Carbohydrates become increasingly relied upon as exercise intensity increases.

Answer

Fat is the primary energy source during high-intensity exercise.

Answer

Protein is the main fuel source during moderate-intensity exercise.

Question 45

Which energy system is primarily used by a marathon runner during the race?

Accepted Answer

Aerobic respiration

Answer

Phosphocreatine system

Answer

Anaerobic glycolysis

Answer

Glycogenolysis