Columbia Sportswear Company has introduced a sweat-activated cooling technology, called Omni-Freeze Zero.

The company says thousands of "little blue rings" embedded in the Omni-Freeze Zero fabric create an instant and prolonged cooling sensation when they come into contact with the wearer's sweat.

The line consists of 40 items of apparel, including footwear and accessories for men and women, ranging from performance shirts to athletic footwear, and from ball caps to snug-fitting briefs. The cooling technology is also incorporated in Columbia's successful line of Performance Fishing Gear (PFG).

"We believe consumers will appreciate the fact that their hard-earned sweat can be used for something more than just passive evaporation," said Columbia's vice president of global marketing, Dan Hanson.

"Everyone knows that Columbia products are great at keeping people warm in the winter; now they can rely on Columbia to help keep them comfortable in the summer with the industry's leading cooling technology. Omni-Freeze Zero is the latest innovation that is helping to transform Columbia into a trusted brand for all seasons."