Here’s a tip: if you’re ever out on a date with a girl and she tells you she’s into Pilates, don’t quip: “Pontius Pilates? Me too!” then immediately start asking her what she thought of Pilates’ philosophical dilemma in Master and Margarita. While it may emit a chuckle around the Down’s Syndrome Algonquin Round Table which you chair, it doesn’t really fly among the exercise set.

Here’s another tip. If you’re into yoga — the most spiritual kind of stretching there is! — make sure you are wearing the properly prescribed black spandex. Via Slate, who’ve been posting lots of cool stories lately, this intriguing expose of the insidious world of designer yoga clothes:

Yoga is all about becoming centered, whole, and at peace; it trains the mind to dispense with extraneous thoughts, such as how you look in your yoga clothes. Unfortunately, this admirable internal quest has lately been complicated by the fact that yoga has become cool and fashionable. In fact, with the possible exception of Pilates, it has become the coolest, most fashionable form of exercise in the country, practiced by people who seem to care a great deal about how they look.

Sportswear companies quickly realized that there was a new market to exploit. Along with the inevitable tops and bottoms, there are skidless towels for yoga mats; meditation cushions (or “zafus”), timers, beads, and gongs; yoga gloves, shoes, bags, eye pillows, and myriad other accoutrements deemed crucial to a proper yoga practice. According to the National Sporting Goods Association, the money spent on tai chi and yoga clothing (the categories are combined) in 2004 was $138 million, up from $79 million just two years ago.

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