Health6 min
FFMI — What It Means and How to Calculate It | Liczbnik
FFMI is a fat-free mass index used by trainers and bodybuilders. Check the formula, reference ranges for men and women, and a worked example.
Blog: Health
Health and fitness: BMI, BMR, TDEE, calorie needs and condition metrics — explained with numbers.
Health7 min
Cutting Diet — How to Set Calories and Macros | Liczbnik
A cutting diet is a controlled calorie deficit with adequate protein intake. See how to calculate calories and macros and avoid the most common mistakes.
Health6 min
Vitamin D Supplementation — Dosage and Rules | Liczbnik
Vitamin D affects bones, immunity, and muscles. Check recommended doses for adults, when to supplement, and what to look for when choosing a product.
Health6 min
Spine Health for Desk Jobs — How to Take Care of It | Liczbnik
Sitting all day strains the spine and weakens postural muscles. Learn how to set up your workstation, which exercises help, and when to take breaks.
Health7 min
Exercise and Heart Health — How to Train Safely | Liczbnik
Physical activity supports cardiovascular health, but it requires a sensible approach. Learn how to choose training intensity and when to get your heart checked.
Health8 min
NFZ Health Insurance in Poland: How to Register | Liczbnik
Registering with NFZ public health insurance in Poland: who is covered, how contributions work, choosing a GP and accessing free treatment.
Health7 min
NFZ Health Card in Poland — How to Use It
Learn how to register with NFZ in Poland, what the health card covers, how to see a GP or specialist, and what waiting times to expect in 2026.
Health7 min
Dental Costs in Poland 2026 — NFZ vs Private
Compare NFZ dental coverage with private clinic prices in Poland 2026. Typical costs for fillings, extractions, implants and check-ups explained clearly.
Health7 min
Private Health Insurance in Poland 2026
Compare private health insurance in Poland 2026: Medicover, Lux Med and Enel-Med plans, monthly premiums from 100 to 400 PLN, and what each plan covers.
Health7 min
GP and Specialist Visits in Poland — Referrals Explained
How to register with a GP in Poland, when you need a referral, private visit costs from 80 to 300 PLN, and how to compare NFZ versus private waiting times.
Health7 min
Prescriptions and Medication Costs in Poland 2026
How prescriptions work in Poland 2026: reimbursed versus full-price medicines, e-prescription system, pharmacy co-payments and generics explained clearly.
Health7 min
How to Calculate BMI and Interpret the Result Correctly
BMI is a simple body mass index. We explain the formula, WHO ranges and show a step-by-step calculation with an example. Check the interpretation.
Health8 min
Calorie Needs — How to Calculate Them (BMR and TDEE)
Learn how to calculate your daily calorie needs. The Mifflin-St Jeor formula, activity multipliers and a step-by-step example you can follow.
Health6 min
How Much Water Should You Drink a Day? Rules for Proper Hydration
How much water a day? Learn hydration norms, a simple formula for your needs and signs of dehydration. A calculation example for your body weight.
Health7 min
Daily Protein Needs — How Much Do You Need
How much protein a day? Norms in grams per kg of body weight, differences for athletes and a calculation example. The best protein sources.
Health6 min
The WHR (Waist-to-Hip) Ratio — How to Calculate It and What It Means
The WHR ratio is the ratio of waist to hip circumference. We explain the formula, norms for women and men and a calculation example. Body shape and risk.
Health7 min
BMR — Basal Metabolic Rate, How to Calculate It
What is BMR and how to calculate it? The Mifflin-St Jeor formula, factors affecting basal metabolism and a step-by-step calculation example.
Health6 min
Due date — how to calculate it with Naegele’s rule
Naegele’s rule step by step: from the first day of your last period add 7 days and subtract 3 months. We explain the formula and show an example.
Health7 min
Pregnancy calendar week by week — a guide
The three trimesters of pregnancy week by week: your baby’s development, changes in mum’s body and key tests. A practical calendar from week 1 to 40.
Health6 min
Fertile days and ovulation — how to calculate them
How to work out your fertile days and ovulation date from your cycle length. We explain the fertile window, the luteal phase and show a worked example.
Health6 min
BMI for children — percentile charts and norms
Why a child’s BMI is read from percentile charts rather than fixed thresholds. We explain percentiles, age norms and show an interpretation example.
Health6 min
Body fat — how to calculate the percentage
Methods for measuring body fat: calipers, BIA and the Deurenberg formula from BMI. We explain the percentage norms and show a worked example.
Health6 min
Blood pressure — norms and how to interpret them
What systolic and diastolic values mean, what the blood pressure norms are and when we talk about hypertension. A practical guide with a table of norms.
Health5 min
Menstrual cycle — how to count its length
How to correctly count the length of your menstrual cycle, what regularity means and when cycle length warrants a consultation. A guide with an example.
Health7 min
How Much Protein a Day? Your Body's Requirement
Find out how much protein your body needs daily in grams per kilogram of body weight, how activity level changes that number, and what shifts during a cut.
Health7 min
How Many Calories Does an Athlete Need — How to Calculate Requirements
How do you calculate an athlete's calorie needs? Learn how many calories you need for running, cycling and strength training, and how diet affects your results.
Health6 min
BMR and TDEE Calculator — How Many Calories Do You Need Per Day
Learn what BMR and TDEE are, how to calculate them, and how to use these metrics to plan your diet and change your weight. Practical examples and a free calculator.
Health6 min
How to Calculate BMI for Children — Percentile Charts and Age Norms
BMI for children is interpreted differently from adults. Learn about percentile charts, how to calculate a child's BMI, and when parents should be concerned.
Health6 min
How to Calculate BMI — Formula, Ranges and What It Means
Learn the BMI formula, understand underweight to obese ranges, see a worked example, and discover the limitations of BMI as a health metric in 2026.