Most people involved in sports evaluate the progress of their workouts primarily by changing their body weight. Losing weight is weighed three times a day, upsetting when recruiting 100 g of water - and happily report that they "dropped 3 kg", not knowing that the weight loss was due to the muscles, not fat.
Also, many are sure that the formula of ideal weight is the growth in centimeters minus one hundred. Based on this figure, they are trying to bring their weight "to perfection."Unfortunately, any such calculations( including BMI), just like the figure on the scales, are more likely to mislead a person.
Perfect fat level
The advanced followers of a healthy lifestyle follow not the total body weight, but the level of body fat, trying to lose weight to "athletic" 8-10%.However, they completely forget that a low percentage of fat does not mean that a person has an ideal sports figure.
Both men in the picture above have the same 8-10% body fat, their weight is about 75 kg, and the height is 180 cm. But if these men are the same in numbers on paper, then visually this is not so. The physical form is a complex concept, and not just a reference to one of the random numbers.
Calculator of ideal weight
The simplest formula for calculating the ideal body weight - the growth in centimeters minus 100 - was deduced in 1850.According to this formula, with an increase of 180 cm, the weight should be 80 kg. However, this method of calculation is very approximate and is suitable only for people above 165 cm.
The Lorentz formula is more accurate: growth - 100 -( (growth - 150) / 4).For a man of 180 cm, she gives 72.5 kg. However, do not rush to look for an online calculator - these formulas have become obsolete long ago, since they do not give an idea of the actual state of the human body. The most commonly used indicator is BMI.
What is the body mass index?
The body mass index( BMI) is an indicator that allows you to indirectly assess whether the weight of a particular person is excessive, normal or inadequate. This indicator was obtained experimentally by the Belgian scientist Adolf Ketele in the distant year of 1869. The
The body mass index is calculated by dividing the weight in kilograms by the squared height in meters( BMI = m / h2).A result of less than 18 means a body weight deficit, 18-25 is the norm, 25-30 is overweight, and a number higher than 30 is obesity( 1).With an increase of 180 cm and a weight of 72.5 kg, the body mass index will be 22.4.
Why does the body mass index not work?
Science has taken a long step forward in a century and a half, since the appearance of the body mass index and the Lorentz formula for calculating weight. These formulas are considered extremely uninformative and are not used by doctors and nutritionists as the main method for determining the ideal weight.
In fact, these calculation methods work only for people suffering from obesity or dystrophy. However, in their case, the error is too high - as a result of one scientific experiment, BMI determined obesity in only 36% of really obese men and 49% of women( 1).Excess weight or excess fat?
It should be remembered that fatty tissue is twice as lighter than muscle. A man who is 180 cm tall and weighs 80 kg can be either a fairly full person or a fit athlete - but the body mass index will be the same in both cases. The key difference will be how much fat in the body.
Body fat percentage( bodyfat percentage ) is the most accurate method for determining the presence of excess weight in a person. To calculate it, you need to know both the total body weight and the fat mass weight, determined with the help of special devices for measuring the fat level.
Determination of the percentage of fat in the body
Above are pictures of different types of male and female figures - focusing on them, you will be able to determine your approximate percentage of fat. The exact figure can be obtained by measuring the subcutaneous fat caliper or special weights with the function of determining the body composition.
Men of athletic build have approximately 6-13% body fat, average "normal" figure is 18-24%, and obesity starts from 25%( 2).In girls, the percentage of fat is much higher - sports physique is characterized by 14-20%, and the average level is 25-30%.
Using formulas to calculate the ideal weight or to determine the body mass index is only suitable for people suffering from obesity or dystrophy. The fat percentage in the body is a more accurate indicator, but it is important not only to know these figures, but to monitor its change with time.
- Body Mass Index, Wikipedia, source
- Body fat percentage, Wikipedia, source