Body mass index (BMI) is a number obtained by dividing the weight in kilograms by the square of the height in meters. It is a widely used international standard to measure the degree of obesity and health. Mainly used for statistical purposes, when we need to compare and analyze the impact of a person's weight on the health of people of different heights, the body mass index value is a neutral and reliable indicator. It is a test item stipulated in the National Students' Physical Health Standard.
The concept of height and body mass index was first put forward by Belgian generalist kettler in the middle of19th century. Its definition is as follows: body mass index (BMI) = weight (kg)/ height (m) 2 For example: 75/( 1.8 2) = 23. 15.