Phase Change of Underwear

This range of undergarments contain quilted pockets filled with a phase change substance with a transition point just around 40C. (above normal body temperature of 37C). Worn underneath the usual assortment of winter clothes, it absorbs heat generated by vigorous human activity, thus reducing over-heating. When the vigorous activity ceases and the cold outside temperature begins to make its presence felt, the pockets undergo phase change back to solid form and release heat back to the body.

Obvious markets would be for winter athletes such as those engaged in sports such as the Biathlon, Cross Country Skiing or Gridiron Football. Tree loggers, hunters and ice fisherman who have to hike to their destinations then have periods of inactivity In the cold could also benefit. Unlike other pocket heaters these are reusable and require no external fuel source.