Health Glossary
Understand BMI, energy expenditure, macros, and training metrics—then open the calculators your readers search for most.
14 terms · Linked from popular calculators on the hub
Categories
BMI (Body Mass Index)
Body compositionDefinition
A weight-to-height ratio used as a screening tool for weight categories. It does not measure body fat directly but correlates with health risk at population level.
Formula
BMI = weight (kg) ÷ height (m)² · US: BMI = 703 × weight (lb) ÷ height (in)²Example
70 kg at 1.75 m → BMI ≈ 22.9 (often labeled “normal” on standard charts).
Why it matters
BMI is a fast checkpoint before deeper metrics (waist, body fat %, labs). Athletes and older adults may need other measures.
Common mistakes
- ✗Treating BMI as a diagnosis
- ✗Ignoring muscle mass or waist circumference
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BMR (Basal Metabolic Rate)
Energy & nutritionDefinition
Estimated calories your body burns at complete rest to maintain vital functions (breathing, circulation, temperature).
Example
A 30-year-old, 70 kg, 175 cm male might show BMR near 1,650–1,750 kcal/day depending on the equation used.
Why it matters
BMR is the floor under TDEE. Cutting far below BMR long-term is usually unsustainable and can backfire.
Common mistakes
- ✗Confusing BMR with total daily burn
- ✗Using BMR alone as a diet calorie target
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TDEE (Total Daily Energy Expenditure)
Energy & nutritionDefinition
All calories burned in a day: BMR plus activity, exercise, digestion (TEF), and minor movement (NEAT).
Formula
TDEE ≈ BMR × activity multiplierExample
BMR 1,700 kcal × 1.55 (moderately active) ≈ 2,635 kcal/day maintenance.
Why it matters
Weight change follows energy balance vs TDEE over weeks—not single-day noise.
Common mistakes
- ✗Overstating activity level
- ✗Expecting scale to move in 2–3 days
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Calorie (kcal)
Energy & nutritionDefinition
The unit used for food energy. “Calories” on labels are kilocalories (kcal): 1 kcal = 1,000 small calories.
Why it matters
Macro and calorie targets only work if portions and logging are consistent.
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Macronutrients (macros)
Energy & nutritionDefinition
Protein, carbohydrates, and fat—the nutrients that provide calories and structure your diet split.
Example
2,000 kcal at 30% protein / 40% carbs / 30% fat ≈ 150 g protein, 200 g carbs, 67 g fat.
Why it matters
Protein supports lean mass; carbs fuel training; fats carry fat-soluble vitamins—balance depends on goals.
Common mistakes
- ✗Chasing ratios without hitting total calories
- ✗Under-eating protein while dieting
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Protein intake
Energy & nutritionDefinition
Dietary protein supports muscle repair, satiety, and enzyme function. Needs rise with training and when losing weight.
Example
75 kg person at 1.6 g/kg/day → about 120 g protein daily.
Why it matters
Adequate protein helps preserve muscle in a deficit—especially with resistance training.
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Body fat percentage
Body compositionDefinition
The share of total mass that is fat tissue. Skinfold, Navy, and bioimpedance methods estimate it differently.
Why it matters
Two people with the same BMI can have very different body composition and health risk.
Common mistakes
- ✗Treating handheld scales as lab accuracy
- ✗Comparing methods that use different formulas
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One-rep max (1RM)
FitnessDefinition
The heaviest weight you can lift once with good form for a given exercise—often estimated from submax sets.
Example
Bench 225 lb for 5 reps might estimate 1RM near 253 lb (Epley-style formula).
Why it matters
1RM estimates program intensity (% of max) without testing true max every week.
Common mistakes
- ✗Using 1RM formulas on high-rep sets (10+)
- ✗Skipping warm-up before true max tests
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Target heart rate zones
CardioDefinition
Training ranges based on max heart rate (often 220 − age) or measured max. Zones map to easy, aerobic, and hard efforts.
Example
Age 40 → estimated max ~180 bpm; “moderate” zone might be ~108–144 bpm (60–80%).
Why it matters
Zones help pace cardio without overdoing intensity every session.
Common mistakes
- ✗Using 220 − age as exact science
- ✗Ignoring medications that affect heart rate
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BAC (blood alcohol content)
WellnessDefinition
Estimated alcohol concentration in blood from drinks, body weight, sex, and time. Impairment rises with BAC; legal limits vary by region.
Why it matters
Planning safe transport and understanding how food, pace, and tolerance change risk.
Common mistakes
- ✗Treating estimates as legal evidence
- ✗Assuming coffee or food instantly “sobers you up”
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Gestational age & due date
PregnancyDefinition
Pregnancy is dated from the first day of the last menstrual period (LMP) in standard obstetric counting, not conception day.
Why it matters
Due-date windows drive prenatal visit timing; ultrasound can adjust dating later.
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Ovulation window
PregnancyDefinition
The fertile window is typically a few days before and through ovulation. Cycle length and luteal phase vary person to person.
Why it matters
Timing intercourse or procedures around ovulation improves conception odds vs calendar guessing alone.
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Daily water intake
WellnessDefinition
Fluid needs depend on weight, climate, activity, and pregnancy/breastfeeding. Urine color and thirst are practical checks.
Why it matters
Dehydration hurts performance and cognition; over-hydration without electrolytes can be risky in extremes.
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Running pace
FitnessDefinition
Time per distance (min/mile or min/km). Pace, speed, and finish time convert each other for race planning.
Example
8:00 min/mile ≈ 7.5 mph; a 10K at that pace ≈ 49:40.
Why it matters
Even pacing prevents blowing up early in races and long runs.
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