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Activewear eliminates sweat with volcanic sand

Swatches | January 1, 2024 | By:

A model wearing the Level Tech Tee with embedded thermoregulating technology in the color Burgundy Heather. Image: Fourlaps

Boulder, Colo.-based company 37.5® Technology has harnessed particles of volcanic minerals and activated carbon from coconuts to create thermoregulating fabrics used in athleisure wear. Clothing brands such as Janji and Fourlaps have incorporated this technology into their apparel, helping athletes keep cool or warm depending on their temperature needs.

Unlike other activewear that wicks away or spreads moisture on the fabric, 37.5 Technology removes it. The inventor of the technology was inspired after visiting Japan in 1992 and burying himself in the volcanic sand baths on Mount Aso. He was surprised that the sand bath was relatively comfortable rather than being too hot. This is because the sand was removing the sweat vapor from his skin, continually cooling him. Volcanic sand absorbs the infrared energy naturally emitted by humans. This removes humidity from the skin before it condenses as sweat, speeding up evaporation. And when it’s cold out, the particles hold in the radiated body heat to keep the wearer warm.

The company’s fibers are designed to biodegrade faster than traditional synthetic fibers, which can take hundreds of years to break down. It has been found that its polyester staple fiber biodegrades 74% in about two years, reducing to volcanic minerals, titanium oxide, carbon dioxide, methane and biomass.

The company is also Global Recycled Standard (GRS)-certified, meaning its products are made with a minimum of 20% recycled materials. 

37.5 Technology is used in active and work apparel, bedding, mattresses, footwear and accessory brands across the U.S. The company’s name derives from the ideal core temperature for optimal performance and comfort, 37.5 C (99.5 F), and the ideal next-to-skin humidity of 37.5%. 

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