Excessive moisture trapped by the composite skin, for example, created condensation dubbed "rain on the plane" that Boeing countered with wicking material.
Upon request, participating hotels provide each guest with complimentary loaner workout gear in a mesh bag: moisture-wicking shirts and shorts to socks and - hooray!
So instead, I use a skin-tight, sweat-wicking polypro base layer on my legs and torso, then the aforementioned fleece layers (which also repel water toward my outer shell).
They stretch in all directions, and like the synthetic base layers worn by skiers and many other athletes, they are breathable (twice as much as cotton) and wicking to remove moisture from the skin.