Last summer, the skirted swimsuit made its big splash back into fashion. This spring, athletic skirts with built-in shorts and briefs are grabbing the what's-hot spotlight.

If you play golf or tennis, you already feel comfortable working out in a skirt. But the newest skirts are designed for women who want to look stylish while they run, hit the gym or even camp out at Starbucks.

On Seventh Avenue in midtown Manhattan last week, the New Balance store windows were filled with skirted mannequins wearing colors like lime green and orange. Spokeswoman Jennifer Hamel says that the Bonita Run Skirt ranks No. 1 out of all New Balance women's apparel in dollar volume for 2007.

The Honolulu New Balance store, in Ward Centre, has almost sold out its running skirts.

At Luke's Locker in Fort Worth, manager Vance Bates reports that sales of Nike skirts and colorful mesh versions from Zoot are moving fast, while at Nordstrom, racks of Nike and Adidas skirts look fresh next to more staid shorts.

And the twin marathon-running sisters who started the California-based company www.run ningshorts.com, offering 24 colors of skirts in two styles (running shorts with briefs and an athletic skirt with shorts) say that their customers range from teenagers to women in their 70s and that recently sales have been doubling almost every month.

What can these skirts do for you that athletic shorts can't?

1. They provide more coverage over the upper thigh, covering what might be a jiggly area with a swingy swath of fabric.

2. Slap on a pair of flats and wear them for summer travel. They're more sophisticated than shorts and pack easily. They also are made from quick-dry fabrics. Rinse them out in your hotel room at night and wear them the next day.

3. They're the hot-weather equivalent of the yoga pant: comfy and versatile. Put them on for your morning power walk and wear them through the day's activities of grocery-store runs and casual lunches.

4. They're stretchy, generally sit low on the waist and are great for expanding, pregnant waistlines.

5. Even if you never wear them to exercise in, they'll make you look cute.