Q.Which parameter is not required to assess the BMR:
i. Weight
ii. Height
iii. Age
iv. Name
🔒You're viewing a preview — the full solution, concept, methods & PYQ mapping are locked.
🔒 Start your 14-day free trial to unlock the full solution →Concept understanding — Basal Metabolic Rate Factors
Basal Metabolic Rate Factors
Think of your body as a house that is always running — lights on, refrigerator humming, AC working, even when everyone is asleep. That constant energy your body burns just to stay alive, without any activity at all, is your Basal Metabolic Rate (BMR). It is the energy needed for breathing, blood circulation, cell production, and maintaining body temperature.
Now, what decides whether your "house" burns energy fast or slow? That is where the factors come in.
The Core Idea
BMR is not the same for everyone. Two people of the same age and weight can have very different BMRs. The factors that influence it are largely biological and cannot be changed by willpower. Understanding them helps explain why some people seem to eat a lot without gaining weight, while others gain weight easily.
Key Factors That Influence BMR
Age — BMR is highest during growth periods like childhood and adolescence. As you age, especially after 20, your BMR gradually declines. This is why older adults often need fewer calories than younger people. The body's metabolic engine naturally slows down.
Gender — Men generally have a higher BMR than women. This is because men typically have more muscle mass and less body fat than women, and muscle tissue burns more energy than fat tissue even at rest. It is not about superiority — it is about body composition.
Body Composition — This is the most important factor. Muscle is metabolically active; it burns calories even when you are doing nothing. Fat tissue is much less active. So a person with more muscle will have a higher BMR than someone with the same weight but more fat. This is why strength training can help increase BMR over time.
Body Size and Surface Area — Larger bodies have higher BMRs because they have more cells to maintain. A taller, heavier person burns more energy at rest than a smaller person. Surface area matters too — more skin means more heat loss, so the body works harder to maintain temperature.
Genetics — Some people are simply born with a faster or slower metabolism. This is inherited and can explain why members of the same family often have similar body types and weight patterns.
Hormones — The thyroid gland is the master controller of metabolism. An overactive thyroid (hyperthyroidism) raises BMR, while an underactive thyroid (hypothyroidism) lowers it. Other hormones like insulin and cortisol also play roles. …
The Mifflin-St Jeor BMR formula this chapter teaches uses weight, height and age as its numerical inputs — a person's name plays no role in the calculation.
Why the other options are wrong …
The BMR formula needs exactly three numerical inputs — weight, height and age (plus sex, to choose the male/female version) — and nothing else, certainly not a name.
The chapter gives the Mifflin-St Jeor BMR Equation as:
Male = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
Female = (10 × body weight in kg) + (6.25 × height in cm) − (5 × age) − 161 …
- CBSE 2026Set 75/SRP1Q/41 markMCQQ.Which of the following statement is correct regarding the Basal metabolic rate ? (A) It is the number of calories needed to maintain energy level during exercise. (B) It is the number of calories needed to maintain the body at movement. (C) It is the number of calories needed to maintain body function at high speed. (D) It is the number of calories needed to maintain body function at rest.
›Reveal solutionSolution
Basal Metabolic Rate (BMR) represents the minimum energy expenditure required to sustain vital body functions when the body is completely at rest, not during exercise or movement.
The concept of Basal Metabolic Rate sits at the heart of understanding human energy needs. Think of your body as a machine that never truly switches off — even when you're lying perfectly still, asleep or resting, your heart continues to beat, your lungs draw breath, your kidneys filter blood, your brain processes signals, and countless cells carry out their maintenance work. All of this invisible activity demands energy, measured in calories. That baseline energy requirement, stripped of any physical activity or digestion, is what we call BMR.
The key word here is "basal," meaning fundamental or base-level. BMR is measured under very specific conditions: the person must be awake but completely at rest, in a neutral temperature environment (so the body isn't expending extra energy to warm or cool itself), and in a post-absorptive state — meaning at least 12 hours after the last meal, so no energy is being used for digestion. These strict conditions ensure we're measuring only the energy needed for essential physiological functions.
Let's examine why the other options miss the mark:
- Exercise and movement (options A and B) immediately disqualify themselves because any physical activity — whether vigorous exercise or simple movement — adds energy expenditure above the basal rate. BMR specifically excludes these activities.
- High speed function (option C) is a misleading phrase. The body's vital functions operate at their normal, steady pace during rest, not at any accelerated "high speed." Increased metabolic rate during stress or activity is something different entirely. …
- CBSE 2024Set 75/RQPS/41 markMCQQ.Given below are two statements labelled Assertion (A) and Reason (R). Assertion (A): The Basal Metabolic Rate (BMR) is the number of calories needed to maintain body function at resting condition. Reason (R): A person who does not engage in any work, still requires energy for the functioning of their internal organs. In the context of the above two statements, which of the following option is correct? (A) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). (B) Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A). (C) Assertion (A) is true, but Reason (R) is false. (D) Assertion (A) is false, but Reason (R) is true.
›Reveal solutionSolution
Both statements are true, and the Reason directly explains why we need a Basal Metabolic Rate — even at complete rest, our organs demand energy to function.
The concept of Basal Metabolic Rate sits at the heart of understanding human energy requirements. Think of your body as a city that never sleeps: even when you are lying perfectly still, doing absolutely nothing, a vast network of processes continues without pause. Your heart pumps blood, your lungs draw breath, your kidneys filter waste, your brain coordinates signals, your liver processes nutrients, and every cell maintains its delicate internal environment. All of this invisible work demands fuel.
Assertion (A) states that BMR is the number of calories needed to maintain body function at resting condition. This is precisely correct. Basal Metabolic Rate represents the minimum energy expenditure required to keep you alive when you are at complete rest — typically measured after a full night's sleep, in a fasting state, in a thermoneutral environment. It accounts for the energy your body burns simply to exist, before you add any physical activity, digestion, or other demands on top.
Reason (R) explains that a person who does not engage in any work still requires energy for the functioning of their internal organs. This is equally true and gets to the biological reality behind BMR. Even if you were to lie motionless for an entire day, your body would still consume a substantial number of calories. The heart alone beats roughly 100,000 times a day; the brain, though only about 2% of body weight, consumes around 20% of resting energy; the liver, kidneys, and other organs all carry out energy-intensive biochemical processes continuously. …
- CBSE 2019Set 75/BVM/41 markQ.On the basis of physiological parameters, mention any two gender differences.
›Reveal solutionSolution
On physiological parameters, males and females differ measurably. Two clear differences: (1) males have a higher basal metabolic rate (BMR) because they carry more lean muscle mass, and (2) males have a higher red blood cell (RBC) count and haemoglobin concentration, giving greater oxygen-carrying capacity.
Concept understanding — what "physiological parameters" means
Males and females share the same body systems, but the systems run at slightly different set-points because of differences in body composition and hormones (chiefly testosterone in males and oestrogen in females). These are averages that describe general trends, not fixed rules about any one person.
Difference 1 — Basal Metabolic Rate (BMR)
BMR is the energy the body uses at complete rest just to stay alive — breathing, circulating blood, and maintaining temperature. Males typically have a higher BMR than females of the same age and weight. The reason is body composition: males carry a greater proportion of lean muscle mass, and muscle tissue burns more energy at rest than fat tissue. This is why energy (calorie) requirements are usually higher for males.
Difference 2 — Red blood cells and haemoglobin …
🎓Unlock everything free for 14 days
- ✓Full step-by-step solutions
- ✓Concept-first explanations
- ✓Methods, shortcuts & mistakes
- ✓PYQ mapping + timed mock tests
Full access for 14 days. No credit card required.