Woolen watch caps have moved from street (think LL Cool J) to treadmill. While the hip headgear is popular with celebs outside the gym — Winona Ryder sported one at a Charlie’s Angels screening, Backstreet Boy AJ McLean is a fan, and Enrique Iglesias wore a ”skullie” (the preferred street term for similar unrolled hats) in his ”Be With You” video — now it’s part of any hot workout. The latest gym-bunny getup includes tank tops, baggy pants, and knit toppers — like striped Paul Frank hats from Urban Outfitters — pulled down to the sweat-drenched eyebrows. The gangsta-at-the-gym look ”provides a really cool, tough, urban alternative” to far less fashionable baseball caps and bandannas, says Michael Redwine, retail director for NYC-based Crunch, which now offers more absorbent all-cotton caps at its in-gym stores. And that’s great news for muscle mavens who’ll never let you see ’em sweat.