Why is underband control so important in sports bra development?

Underband control is important because it strongly affects both support and comfort. If the underband is too loose, the bra may not provide enough hold. If it is too tight, it can create pressure, rolling, or discomfort during movement. The right underband depends on support level, elastic quality, fabric recovery, body coverage, and size range. For sports bra samples, underband feel should be reviewed together with strap tension and neckline security.