Basal metabolic rate (BMR) MCQs With Answer

Basal metabolic rate (BMR) MCQs With Answer are essential study tools for B. Pharm students preparing for pharmacology, therapeutics, and clinical practice exams. This concise, keyword-rich introduction covers BMR definition, measurement methods (indirect calorimetry), standard conditions, influencing factors (age, sex, body composition, thyroid status), and common predictive equations (Harris-Benedict, Mifflin-St Jeor). Understanding BMR helps predict drug metabolism, dosing considerations, nutritional requirements, and energy balance in patients. The following targeted questions deepen conceptual knowledge and application skills, reinforce calculations, and clarify differences between BMR, RMR, and total energy expenditure. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. What is the definition of basal metabolic rate (BMR)?

• The rate of energy expenditure while sleeping
• The minimum energy expenditure to sustain vital functions in a rested, post-absorptive, thermoneutral state
• Energy expenditure during moderate exercise
• Energy required to digest a standard meal

Correct Answer: The minimum energy expenditure to sustain vital functions in a rested, post-absorptive, thermoneutral state

Q2. Which condition is required when measuring true BMR?

• Postprandial state within 2 hours of a meal
• Active exercise immediately before measurement
• Post-absorptive state, quiet rest, thermoneutral environment
• Cold exposure to stimulate thermogenesis

Correct Answer: Post-absorptive state, quiet rest, thermoneutral environment

Q3. Which method is considered the gold standard for measuring BMR?

• Bioelectrical impedance analysis
• Indirect calorimetry measuring O2 consumption and CO2 production
• Skinfold thickness measurement
• Harris-Benedict predictive equation

Correct Answer: Indirect calorimetry measuring O2 consumption and CO2 production

Q4. Which hormone most increases basal metabolic rate?

• Insulin
• Thyroid hormones (T3/T4)
• Aldosterone
• Parathyroid hormone

Correct Answer: Thyroid hormones (T3/T4)

Q5. Which factor decreases BMR?

• Fever
• Hyperthyroidism
• Starvation and severe caloric restriction
• Growth hormone excess

Correct Answer: Starvation and severe caloric restriction

Q6. The Harris-Benedict equation is used to:

• Directly measure oxygen consumption
• Predict basal or resting energy expenditure using weight, height, age, and sex
• Estimate fat mass from skinfolds
• Calculate body surface area only

Correct Answer: Predict basal or resting energy expenditure using weight, height, age, and sex

Q7. Which is a limitation of predictive BMR equations?

• They measure real-time oxygen consumption
• They do not account for individual variations in body composition and organ mass
• They are always more accurate than indirect calorimetry
• They directly assess thyroid function

Correct Answer: They do not account for individual variations in body composition and organ mass

Q8. Resting metabolic rate (RMR) differs from BMR mainly because RMR:

• Is measured under stricter conditions than BMR
• Usually requires a longer fast than BMR
• Is measured under less strict conditions and is slightly higher than BMR
• Refers only to energy used during sleep

Correct Answer: Is measured under less strict conditions and is slightly higher than BMR

Q9. Which organ has the highest specific metabolic rate per unit mass?

• Skeletal muscle
• Adipose tissue
• Brain
• Bone

Correct Answer: Brain

Q10. How does increased lean body mass affect BMR?

• Decreases BMR because muscle uses less energy
• Increases BMR because metabolically active tissue consumes more energy
• No effect on BMR
• Only affects BMR in children

Correct Answer: Increases BMR because metabolically active tissue consumes more energy

Q11. Which clinical situation commonly raises BMR?

• Hypothyroidism
• Sepsis and severe infection
• Malnutrition
• Hypothermia

Correct Answer: Sepsis and severe infection

Q12. Units typically used to express BMR are:

• mg/dL
• kcal/day or kJ/day
• mmHg
• beats per minute

Correct Answer: kcal/day or kJ/day

Q13. Which predictive equation is newer and often more accurate for modern populations?

• Broca index
• Mifflin-St Jeor equation
• Quetelet formula

Correct Answer: Mifflin-St Jeor equation

Q14. Indirect calorimetry estimates energy expenditure by measuring:

• Body temperature and blood pressure
• Oxygen consumption and carbon dioxide production
• Skinfold thickness and waist circumference
• Urine nitrogen only

Correct Answer: Oxygen consumption and carbon dioxide production

Q15. Which gas exchange parameter is most directly linked to energy substrate utilization?

• Respiratory quotient (RQ)
• Minute ventilation only
• Blood oxygen saturation
• Hemoglobin concentration

Correct Answer: Respiratory quotient (RQ)

Q16. An RQ of approximately 1.0 indicates predominant metabolism of which substrate?

• Fat
• Protein
• Carbohydrate
• Ketone bodies

Correct Answer: Carbohydrate

Q17. In prolonged fasting, BMR typically:

• Increases due to gluconeogenesis
• Remains unchanged
• Decreases as adaptive thermogenesis reduces energy expenditure
• Becomes unpredictable and doubles

Correct Answer: Decreases as adaptive thermogenesis reduces energy expenditure

Q18. Which drug class is known to increase BMR through sympathetic stimulation?

• Beta-blockers
• Benzodiazepines
• Thyroid hormone analogs and sympathomimetics
• Anticholinergics only

Correct Answer: Thyroid hormone analogs and sympathomimetics

Q19. Which statement about surface area and BMR is correct?

• BMR is directly proportional to body surface area; smaller animals have higher metabolic rate per kg
• Surface area has no relation to metabolic rate
• Larger surface area always means lower absolute BMR
• BMR depends only on height, not surface area

Correct Answer: BMR is directly proportional to body surface area; smaller animals have higher metabolic rate per kg

Q20. In which patient condition would predictive equations most likely be inaccurate?

• Healthy young adult
• Critically ill ICU patient with sepsis and organ failure
• Sedentary office worker
• Average elderly outpatient

Correct Answer: Critically ill ICU patient with sepsis and organ failure

Q21. What is the clinical relevance of BMR in pharmacokinetics?

• BMR directly determines drug pKa
• BMR influences energy expenditure but has no pharmacokinetic relevance
• BMR may affect metabolism and clearance by altering hepatic blood flow and enzyme activity
• BMR only affects topical drug absorption

Correct Answer: BMR may affect metabolism and clearance by altering hepatic blood flow and enzyme activity

Q22. Which population typically has the highest per-kg BMR?

• Elderly men
• Obese adults based on total weight
• Infants and young children
• Postmenopausal women

Correct Answer: Infants and young children

Q23. Which statement about adipose tissue and BMR is true?

• Adipose tissue has higher metabolic activity per kg than muscle
• Adipose tissue contributes minimally per unit mass but increases total BMR when abundant
• Fat-free mass does not influence BMR
• Only visceral fat affects BMR, subcutaneous fat does not

Correct Answer: Adipose tissue contributes minimally per unit mass but increases total BMR when abundant

Q24. Which factor does NOT significantly affect BMR?

• Age
• Ambient temperature within thermoneutral range
• Sex
• Thyroid status

Correct Answer: Ambient temperature within thermoneutral range

Q25. Which clinical measurement can be used to estimate lean body mass and thus better predict BMR?

• Serum creatinine correction for renal function
• Dual-energy X-ray absorptiometry (DEXA)
• Random blood glucose
• Electrocardiogram

Correct Answer: Dual-energy X-ray absorptiometry (DEXA)

Q26. The thermic effect of food (TEF) represents roughly what percentage of total daily energy expenditure?

• 50–60%
• 20–30%
• 5–10%
• 0–1%

Correct Answer: 5–10%

Q27. Which equation requires body weight, height, age, and sex to estimate RMR?

• Body Mass Index formula
• Mifflin-St Jeor equation
• Wagner equation for renal clearance
• Fick’s law

Correct Answer: Mifflin-St Jeor equation

Q28. In hyperthyroidism, BMR changes how?

• Decreases due to receptor downregulation
• Increases markedly due to upregulated metabolic processes
• Remains the same
• Varies only with exercise

Correct Answer: Increases markedly due to upregulated metabolic processes

Q29. Which measurement best distinguishes BMR from physical activity energy expenditure?

• 24-hour dietary recall
• Indirect calorimetry performed at rest under controlled conditions
• Blood pressure monitoring
• Skin temperature mapping

Correct Answer: Indirect calorimetry performed at rest under controlled conditions

Q30. For BMR measurement, the fasting period required is typically:

• 2–3 hours
• At least 12 hours (overnight fast)
• Less than 30 minutes
• No fasting required

Correct Answer: At least 12 hours (overnight fast)

Q31. Which population has lower average BMR when adjusted for body composition?

• Young athletic men
• Obese individuals with high fat mass
• Women compared to men due to lower lean mass
• Children compared to adults

Correct Answer: Women compared to men due to lower lean mass

Q32. Which clinical intervention can acutely raise BMR?

• Administration of beta-blockers
• Cooling the patient to hypothermia
• Giving levothyroxine to a hypothyroid patient
• Severe caloric restriction

Correct Answer: Giving levothyroxine to a hypothyroid patient

Q33. Which organ contributes disproportionately to resting energy expenditure despite small mass?

• Skin
• Liver
• Adipose tissue
• Cartilage

Correct Answer: Liver

Q34. Which test component is not part of standard indirect calorimetry for BMR?

• Measurement of VO2
• Measurement of VCO2
• Continuous ECG monitoring for arrhythmias
• Calibration of gas analyzers

Correct Answer: Continuous ECG monitoring for arrhythmias

Q35. The presence of shivering during measurement will:

• Have no effect on BMR
• Lower the measured BMR
• Artificially raise the measured BMR
• Only affect RQ

Correct Answer: Artificially raise the measured BMR

Q36. Which nutritional state increases protein catabolism and may change BMR?

• Balanced calorie surplus
• Prolonged fasting or starvation
• Postprandial anabolic state
• Acute hyperhydration

Correct Answer: Prolonged fasting or starvation

Q37. BMR per kg of body weight is typically higher in:

• Obese adults compared to lean adults
• Females compared to males of same weight
• Children compared to adults
• Older adults compared to young adults

Correct Answer: Children compared to adults

Q38. Which of the following reduces accuracy of a single BMR measurement?

• Standardized overnight fast
• Recent caffeine or nicotine intake
• Thermoneutral environment
• Quiet restful awake state

Correct Answer: Recent caffeine or nicotine intake

Q39. Which term best describes the additional calories expended during physical activity above RMR?

• Basal energy requirement
• Thermic effect of food
• Activity energy expenditure
• Resting energy balance

Correct Answer: Activity energy expenditure

Q40. When calculating caloric needs for weight maintenance, total energy expenditure includes:

• Only BMR
• BMR plus thermic effect of food and physical activity
• Only calories burned during exercise
• Urinary nitrogen excretion alone

Correct Answer: BMR plus thermic effect of food and physical activity

Q41. In obesity pharmacotherapy, why is understanding BMR useful?

• BMR determines drug taste
• BMR helps tailor caloric targets and may influence drug dosing via metabolic rate and clearance
• BMR replaces need for therapeutic monitoring
• BMR predicts drug-induced QT prolongation

Correct Answer: BMR helps tailor caloric targets and may influence drug dosing via metabolic rate and clearance

Q42. Which electrolyte disturbance commonly decreases BMR?

• Hypernatremia
• Hypocalcemia
• Hypothyroid-related hyponatremia is indirectly associated
• Hyperkalemia directly increases BMR

Correct Answer: Hypothyroid-related hyponatremia is indirectly associated

Q43. Which clinical scenario may falsely elevate measured BMR if not controlled?

• Measurement after overnight rest and fasting
• Measurement during acute pain or anxiety
• Measurement in thermoneutral room with calm patient
• Measurement with properly calibrated equipment

Correct Answer: Measurement during acute pain or anxiety

Q44. Which intervention is used to lower elevated BMR in hyperthyroid patients?

• Give high-dose thyroid hormone
• Thionamides (methimazole) and beta-blockers
• Increase calorie intake only
• Induce fever

Correct Answer: Thionamides (methimazole) and beta-blockers

Q45. Which statement about gender differences in BMR is accurate?

• Women always have higher BMR than men of same age and body composition
• Men typically have higher BMR due to greater lean body mass
• There is no gender difference once adjusted for height
• Gender differences are solely due to activity levels

Correct Answer: Men typically have higher BMR due to greater lean body mass

Q46. How does fever affect BMR?

• Fever decreases BMR due to lethargy
• BMR increases approximately 7% per 1°C rise in body temperature
• Fever has no measurable effect on metabolic rate
• Fever only affects RQ, not BMR

Correct Answer: BMR increases approximately 7% per 1°C rise in body temperature

Q47. Which is true about organ contributions to BMR?

• Kidneys and liver contribute little to resting energy expenditure
• Organs like liver, brain, heart, and kidneys contribute disproportionately more per mass than muscle
• Skeletal muscle always dominates per-unit mass metabolic rate
• Adipose tissue has the highest organ metabolic contribution

Correct Answer: Organs like liver, brain, heart, and kidneys contribute disproportionately more per mass than muscle

Q48. In clinical nutrition, measuring BMR helps to:

• Decide antibiotic choice
• Estimate baseline caloric needs to design feeding regimens
• Diagnose cancer directly
• Replace the need for anthropometry

Correct Answer: Estimate baseline caloric needs to design feeding regimens

Q49. Which factor would lead to underestimation of BMR when using a predictive equation?

• High proportion of lean mass compared to average population used to derive the equation
• Using indirect calorimetry instead of equation
• Equation derived from similar demographic group
• Accurate height and weight input

Correct Answer: High proportion of lean mass compared to average population used to derive the equation

Q50. Which measurement is most useful to monitor metabolic response in critically ill patients?

• Single fasting glucose level
• Serial indirect calorimetry to measure changes in energy expenditure
• Only body weight daily
• Skinfold measurements every hour

Correct Answer: Serial indirect calorimetry to measure changes in energy expenditure

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com