Mirror, Mirror: Looking good at the gym, and later

Here we are, four days into the new year, and you're going hard on your resolutions: eating healthier, meditating, and, of course, working out. You dream of a tight core and doing the Broad Street Run.

How can fashion help you?

This month, apparel companies are introducing their spring collections of workout gear aimed at keeping us stylish before, during, and after we cycle.

To stay fit and focused, we need to hit the gym in between grocery shopping, picking up dry cleaning, and having cocktails. A simple T-shirt and yoga pants just won't do. So companies such as lululemon, Athleta, and Under Armour are producing collections that rival those on New York's runways.

Think bold-colored, body-hugging tanks layered under racer-back tops with empire waists or long-sleeved T's and pants - boot-cut and skinny versions - that mold to our bottoms better than a pair of Lucky Brand jeans.

"People want versatility in their clothing so they can go on with the rest of their activities," explained Tracy Byrnes, senior manager of innovation for Athleta, the women's athletic apparel brand owned by Gap Inc. that opened a specialty shop on Walnut Street late last summer.

Layering is key, Barnes said, as she pointed out Athleta's Contender skirt - a pair of running pants attached to a miniskirt that looks like a leggings/miniskirt combo.

The company also sells tights in denim hues that can double as jeggings.

Lauren Boggi, owner of the Philadelphia-based Lithe Method workout franchise, introduced Lithe Wear in the spring. Boggi created the 12-piece line of slightly goth workout wear that includes leather leggings (not exactly sure what it would feel like running in those) and lace capris.

"A lot of times I have meetings after work and if I'm teaching in my leather leggings all I have to do is wash my face, change my shoes into heels, and I look great," Boggi says. "Nobody can tell the difference."

To help you get your workout on at the dawn of 2012, we've compiled a list of must-have pieces from apparel manufacturers that will help you look fantastic as you work on being fit.

Athleta