The most common method to figure out whether you have the normal ratio of height and weight, is a method of calculating the Quetelet index, body mass index. This index is equal to the ratio of body weight in kilograms to the square of the height in meters.For example, if a person weighs 50 kg, and the growth of his 165 cm, then BMI = 50/1,652 = 50/2,7225 = 18,4.
If the body mass index is in the range of 20-25, then the person has a normal weight for their height. In our example, there is a shortage of weight. The real problems with excess weight say BMI > 30.
A different ratio between weight and height is established by the formula Brock. The formula of Broca allows you to set the ideal weight for the three types of people. Low people (under 165 cm) calculate the ideal weight according to the formula: weight = growth in cm - 100 cm for People of average height (166 - 174 cm) take an additional 5 cm: weight = growth in cm - 105 cm. Tall people (175 cm) should have a weight: weight = growth in cm - 110 cm Back to our example and see that the growth of 165 cm should have a weight of 165 - 100 = 65 kg.
These two formulas have some disadvantage, they do not take into account the body type of the person. Science identifies three body type: asteniki, normostenik and hypersthenic. Body type can be identified by the method Solovyov, measuring the circumference of your wrist. Women astenikov wrist thinner than 15 cm (for men - 18 cm), women normostenikov wrist circumference can be 15 to 17 cm (for men and 18-20 cm), giperstenikov more than 17 cm (males over 20 cm).The Broca formula is calculated for normostenikov. For asthenic body type of its result must subtract 10% and hypersthenic - add 10%.