These rules also banned suits which go above the navel or below the knee for men and suits which extend past the shoulders or cover the neck for women FINA stated that it "wishes to recall the main and core principle is that swimming is a sport essentially based on the physical performance of the athlete". Suits Bodyskin A bodyskin is a style of competitive swimwear worn by both female and male athletes. Bodyskins are normally made of technologically advanced lycra-based fabrics designed to hug the body tightly and provide increased speed and decreased drag resistance in the water. The bodyskin resembles the design of a dive skin, commonly used by snorkelers and scuba divers for warm weather climates. The primary distinguishing feature is the material from which the bodyskin suit is made. Some bodysuits provide full body coverage from the ankles to the neck and wrists, such as Ian Thorpe's adidas JETCONCEPT bodysuit which made its debut in 2003, Thorpe previously wore an earlier Adidas black bodysuit design in the 2000 Summer Olympics. Sleeveless designs such as the Speedo LZR Racer was popular in the 2008 Summer Olympics; Speedo also produces a bodyskin designed specifically for the backstroke. Other competing bodysuits include Acquablade, Fastskin, and Sharkskin, which are produced by Mizuno, Asics, Descente, Arena, and Nike. Swimmers reported that bodyskins improved buoyancy. This is true as long as the suits remain dry. As such, they are recommended for distances under 200m. The national coach of a small country stated that the suits need exact sizing and resulting high cost "increas[ed] the disparity between the haves and have nots." As with most technologically advanced fabric swimwear, bodyskins were only commonly used at highly competitive levels of the swimming sport and are known to sell for prices in excess of US$400. Despite their cost, a single bodysuit can only be used for a handful of races, as getting in and out of the suit repeatedly would damage its form-fitting properties, memorably when Ian Thorpe tore his Adidas bodysuit right before the 4x100 men's freestyle relay podium ceremony in the 2000 Summer Olympics. FINA rule changes Bodyskins were banned from FINA competitions from the start of 2010 after many national swimming federations demanded the action, and leading athletes such as Michael Phelps and Rebecca Adlington criticised the suits. They continue to be used for other purposes, including research. Briefs A swim brief