What is the purpose of belts on ski jumping suits?
The purpose of the belt is to prohibit athletes from pulling their suits down before they jump. By getting the crotch of their suits lower, athletes can increase their lift during the flight giving them an unfair advantage. If you have any further questions about the belt or how it should be installed, email Anders Johnson at firstname.lastname@example.org
Inside the suit just above the hip bones of the athlete a non-stretchable strap must be sown around horizontally from zipper to zipper. This strap must be 2-4cm wide and maximum 2mm thick.
The measured circumference of this part of the suit – 5cm above and 5cm below the lower seam of the strap, incl. the strap itself, even when the suit is stretched, must not exceed the respective body measurement. The transition from the close-fitted part of the suit (+/- 5cm from the strap) to the allowed tolerance in the suit size must be gradual, without and additional curves
**This is the most up-to-date FIS rules for Jump Suit Belts and their fitting**