So, I decided to check out Gap, Old Navy, and Athleta — all owned by Gap Inc. — in search of the perfect high-rise, full-length black leggings. Here's how it went. I started my search at Gap.

And with good reason: Their bestselling Align leggings are great. I own several pairs, and they're soft and smooth, with plenty of stretch. But Lululemon isn't the only game in town, you know? I ...