The Body Mass Index (BMI) is a measure that is used to determine if a person is underweight, normal weight or overweight. The BMI is a statistical factor that is calculated using the bodyweight and height. Formula: BMI = weight (kg) / height² (m²)

In skijumping the so-called BMI-rule was introduced in 2004 after a public discussion about the underweight of some jumpers and the danger of anorexia. Since then, jumpers have to obtain a BMI of at least 21 if weighed with equipment or they have to use shorter skis. Not following this rule results in disqualification.