Final answer:
The fiber with extreme elastic properties used in athletic clothing is often made from materials like elastin and synthetic polymers such as nylon and polyester, offering flexibility, durability, and moisture-wicking capabilities.
Step-by-step explanation:
A fiber with extreme elastic properties that is used for athletic clothing is typically one that contains a high percentage of elastin. Elastin is a protein that gives fibers the ability to return to their original shape after being stretched or compressed, which is essential for the dynamic movements in sports. These elastic fibers are a key part of various textile products, including those found in the elastic ligaments of the vertebral column and in the skin. One such synthetic fiber that is commonly used in athletic wear due to its elasticity and strength is nylon. Nylon is known for its toughness, high tensile strength, wrinkle resistance, and the ability to retain its shape, which makes it ideal for athletic apparel that requires flexibility and durability. Another type of synthetic fiber that offers elasticity is polyester, which is also widely used for sports clothing due to its resistance to stains and ability to wick moisture.