Exercise physiology Practice Questions

Question 1

A 35-year-old woman presents to the clinic for a several-month history of heat intolerance. She lives in a small apartment with her husband and reports that she always feels hot and sweaty, even when their air conditioning is on high. On further questioning, she's also had a 4.5 kg (10 lb) unintentional weight loss. The vital signs include: heart rate 102/min and blood pressure 150/80 mm Hg. The physical exam is notable for warm and slightly moist skin. She also exhibits a fine tremor in her hands when her arms are outstretched. Which of the following laboratory values is most likely low in this patient?

Accepted Answer

Thyroid-stimulating hormone

Answer

Triiodothyronine (T3)

Answer

Thyroxine (T4)

Answer

Calcitonin

Answer

Glucose

Question 2

A scientist is trying to design a drug to modulate cellular metabolism in the treatment of obesity. Specifically, he is interested in understanding how fats are processed in adipocytes in response to different energy states. His target is a protein within these cells that catalyzes catabolism of an energy source. The products of this reaction are subsequently used in gluconeogenesis or β-oxidation. Which of the following is true of the most likely protein that is being studied by this scientist?

Accepted Answer

It is stimulated by epinephrine

Answer

It is inhibited by glucagon

Answer

It is inhibited by acetylcholine

Answer

It is inhibited by cortisol

Answer

It is stimulated by insulin

Question 3

A healthy 22-year-old male participates in a research study you are leading to compare the properties of skeletal and cardiac muscle. You conduct a 3-phased experiment with the participant. In the first phase, you get him to lift up a 2.3 kg (5 lb) weight off a table with his left hand. In the second phase, you get him to do 20 burpees, taking his heart rate to 150/min. In the third phase, you electrically stimulate his gastrocnemius with a frequency of 50 Hz. You are interested in the tension and electrical activity of specific muscles as follows: Biceps in phase 1, cardiac muscle in phase 2, and gastrocnemius in phase 3. What would you expect to be happening in the phases and the respective muscles of interest?

Accepted Answer

Increase of tension in all phases

Answer

Increase of tension in experiments 2 and 3, with the same underlying mechanism

Answer

Recruitment of large motor units followed by small motor units in experiment 1

Answer

Fused tetanic contraction at the end of all three experiments

Answer

Recruitment of small motor units at the start of experiments 1 and 2

Question 4

An 83-year-old male presents with dyspnea, orthopnea, and a chest radiograph demonstrating pulmonary edema. A diagnosis of congestive heart failure is considered. The following clinical measurements are obtained: 100 bpm heart rate, 0.2 mL O2/mL systemic blood arterial oxygen content, 0.1 mL O2/mL pulmonary arterial oxygen content, and 400 mL O2/min oxygen consumption. Using the above information, which of the following values represents this patient's cardiac stroke volume?

Accepted Answer

40 mL/beat

Answer

30 mL/beat

Answer

70 mL/beat

Answer

60 mL/beat

Answer

50 mL/beat

Question 5

A 27-year-old man is running on the treadmill at his gym. His blood pressure prior to beginning his workout was 110/72. Which of the following changes in his cardiovascular system may be seen in this man now that he is exercising?

Accepted Answer

Decreased systemic vascular resistance

Answer

Decreased blood pressure

Answer

Increased systemic vascular resistance

Answer

Decreased stroke volume

Answer

Decreased heart rate

Question 6

A 24-year-old man is running a marathon. Upon reaching the finish line, his serum lactate levels were measured and were significantly increased as compared to his baseline. Which of the following pathways converts the lactate produced by muscles into glucose and transports it back to the muscles?

Accepted Answer

Cori cycle

Answer

Citric acid cycle

Answer

Glycolysis

Answer

Glycogenesis

Answer

Pentose phosphate pathway

Question 7

During a clinical study examining the diffusion of gas between the alveolar compartment and the pulmonary capillary blood, men between the ages of 20 and 50 years are evaluated while they hold a sitting position. After inhaling a water-soluble gas that rapidly combines with hemoglobin, the concentration of the gas in the participant's exhaled air is measured and the diffusion capacity is calculated. Assuming that the concentration of the inhaled gas remains the same, which of the following is most likely to increase the flow of the gas across the alveolar membrane?

Accepted Answer

Treadmill exercise

Answer

Deep exhalation

Answer

Entering a cold chamber

Answer

Standing straight

Answer

Assuming a hunched position

Question 8

A 19-year-old male soccer player undergoes an exercise tolerance test to measure his maximal oxygen uptake during exercise. Which of the following changes are most likely to occur during exercise?

Accepted Answer

Decreased physiologic dead space

Answer

Increased apical ventilation-perfusion ratio

Answer

Decreased alveolar-arterial oxygen gradient

Answer

Increased arterial partial pressure of oxygen

Answer

Increased pulmonary vascular resistance

Question 9

A person is exercising strenuously on a treadmill for 1 hour. An arterial blood gas measurement is then taken. Which of the following are the most likely values?

Accepted Answer

pH 7.57 PaO2 100, PCO2 23, HCO3 21

Answer

pH 7.56, PaO2 100, PCO2 44, HCO3 38

Answer

pH 7.32, PaO2 42, PCO2 50, HCO3 27

Answer

pH 7.38, PaO2 100, PCO2 69 HCO3 42

Answer

pH 7.36, PaO2 100, PCO2 40, HCO3 23

Question 10

A 36-year-old woman is admitted to the hospital for the evaluation of progressive breathlessness. She has no history of major medical illness. Her temperature is 37°C (98.6°F), pulse is 110/min, and respirations are 22/min. Pulse oximetry on room air shows an oxygen saturation of 99%. Cardiac examination shows a loud S1 and S2. There is a grade 2/6 early systolic murmur best heard in the 2nd right intercostal space. Cardiac catheterization shows a mixed venous oxygen saturation of 55% (N= 65–70%). Which of the following is the most likely cause of this patient's breathlessness?

Accepted Answer

Decreased left ventricular ejection fraction

Answer

Increased peripheral shunting

Answer

Decreased hemoglobin concentration

Answer

Increased carbon dioxide retention

Answer

Increased pulmonary vascular resistance

Exercise physiology

Study Resources

Lessons

Questions

Flashcards

Lessons

Muscle fiber types and recruitment

Energy systems during exercise

Oxygen consumption and VO2 max

Cardiovascular responses to exercise

Respiratory adaptations during exercise

Metabolic changes with exercise

Acid-base balance during exercise

Thermoregulation during exercise

Exercise training adaptations

Fatigue mechanisms

Exercise testing principles

Exercise in environmental extremes

Exercise in special populations

Practice Questions

Flashcards

About Exercise physiology for USMLE

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