Embodiments of the invention may include one or more high-density textile fibers with a density from about 1 to about 11 g/mL. Some embodiments may include fabrics and/or garments made from such fibers. Embodiments comprising garments can include, for instance, exercise aids for providing extra mass to the wearer. Other embodiments can comprise, without limitation, building materials, safety equipment, armor, body armor, protective apparel, marine repair materials, marine protective devices, boat hulls, vehicle chassis, or blast-resistant materials.