What type of fabric is prohibited for supportive shirts?

Supportive shirts in powerlifting are designed to provide assistance during lifts, but there are specific guidelines regarding the materials that can be used to maintain fairness and integrity in competition. The prohibition of stretch fabric for supportive shirts is based on the intention to prevent excessive elasticity that could enhance performance beyond the rules of the sport.

Stretch fabric typically allows for more movement and flexibility, potentially giving athletes an unfair advantage by improving their lifting capacity. The regulations are in place to ensure that the gear used does not compromise the traditional aspects of lifting or distort the competition's level playing field.

In contrast, while cotton and polyester are common materials for athletic wear, they are not banned because they do not offer the same type of structural enhancement that stretch fabrics do. Sleepwear fabric is also not a typical choice for competitive lifting due to its design and function, but it does not come into play in the context of supportive gear under the rules.

Thus, the prohibition focuses specifically on the characteristics of stretch fabric that could interfere with the sport's principles and standards.