Okay, so here's the deal (I approach exercise with the same "I don't go to the gym to be a pussy" attitude, so I think I can help): yoga can be really great. I go to a fancy gym where women and gay men take their yoga super seriously. Don't be intimidated by the stretchy capri pants. If you can get past that, everything will be okay.

I started doing yoga in the fall and now if I go a week or two without hitting it up, my body can feel the difference. I usually only do it once or maybe twice a week after a workout (spin or run) and that's enough for me. Anyway, the answer to your question is no, doing yoga will not make you a granola-eating pussy. I guess the granola-eating pussies can't afford my gym, and judging by the selection of yoga offerings you mentioned, they probably can't afford yours either. Most of the people I practice with are protein-eating athletes.

My advice would be to start with hatha. Truth be told, I've only done that and power (oh and the one with the balls just sounds like pilates which is okay but I'd start old school without the balls), and those are just fine. Stay away from the heated yoga - that is just trendy yoga for wanna be celebs. As for a mat, umm, you should practice with one but you should try to hold out until you know if you are going to continue with it before buying. Maybe your gym rents them out? Hatha is good for beginners. Oftentimes, the instructor will ask if there are any beginners and you should raise your hand and they will hopefully be extra nice to you.

I'll be honest, it takes a while to get past the "this is a waste of time, I am not even sweating, hmm I'm bored I wonder what's for dinner" feeling, but that is why you are using it as a supplement to (and not a replacement for) real exercise. Once you embrace it for what it is (extra-long stretching session, muscle-toning, mind-clearing), you might start to love it. Phew - hope that helps :)

Oh also the blocks and the straps? They will help you become more bendy.

P.S. I just saw that you might want to buy clothes. In that case, embrace the stretchy capri pants. I bought a most excellent pair from GAP BODY and now I never take them off.

All I can tell you is that heated yoga is associated with some yogi asshole who's tried to patent his particular brand of the discipline. Yoga with a bad IP policy should be avoided, lest you incur the wrath of nerds such as myself.

Also, thank you for the creaky-knee eliptical machine caveat. But it's okay; I realize I'm not exactly at my most masculine when I'm using that machine.

I guess I'd just say don't be scared. Yoga is great because you are the one ultimately in control of your body and what you do with it -- how far you reach, how deep you stretch, how long you hold a pose. My experience is that most instructors ask at the beginning of a class if anyone's new, and they do their best to be reassuring. I mean, think back to the first time you got on the spin bike -- you didn't know the hand positions or how to jump or any of that stuff. So it's kind of the same thing: it'll take a little time to be "good," but that's okay.
Like your friend says above, I'd say hatha is probably a fine place to start. Ashtanga might be good, too, although it's sometimes faster-paced, so maybe work up to that. I'm not a fan of bikram (the hot yoga) AT ALL, but some people swear by it.

I'd imagine that your gym probably provides mats of some sort. They're probably not the thin, sticky kind that you'll see some folks with, but if you're just trying it out, go with what's free, right? As for clothes, you want to wear something that's going to stay close to your body when you're bent over. So a tank top is probably a good bed, and bottoms long enough so that you're not going to feel super-self-conscious when your, well, bottom is sticking up in the air. The gym probably provides blocks and straps, also, but it's doubtful the instructor will even use them.

I think you'll find yoga is a really nice complement to running, as it stretches out your hamstrings and calves. Plus, the breath control is actually pretty useful when doing cardio.
Starting to sound a bit boosterish here, so I'll hush. But give it a go or three and keep us posted on the result. (And different instructors have vastly different styles, so don't write it off wholesale if you don't like the person you go to first.)

I second Matt's advice to try different instructors. Even instructors for the same style can be very different. As a beginner, I'd recommend looking for an instructor who is really interested in proper form and not as focused on rapidly switching between different positions. While the latter can be a good workout, if you're not doing the poses with the proper form, you might not be getting as much benefit anyway or could get hurt. (You can feel a big difference with poses with just minor adjustments. I remember there was one pose I never got much out of until the instructor came by and adjusted my hip by about a half inch and it was like "Wow! So that's the big deal!") I've had some good yoga instructors at my gym but, unfortunately, I've found the yoga instructors at a lot of gyms don't care about form as much as the ones at yoga studios.

You could always do something somewhere between yoga and "gym"...like bellydancing! Or swimming. There ARE other options (can you tell I kinda agree with you about the wussiness of yoga? I just get really, really bored. And you can't ever COMPLETE it. You can't be all "I won yoga!". blah).

You might want to try pilates. I'm more aerobic-oriented, too, but I canceled my expensive gym membership and can't run outside in winter, so one day I bought a pilates tape. Yoga is way way too low-key for me; I would just fall asleep. Pilates is slightly more stimulating and it makes your muscles look GREAT.

try the mtv yoga dvd w/the brown haired chick from the real world. i've only found a few yoga classes i really enjoy given i am more a go out there and hit some stuff kinda excerciser and this is *the only* dvd i have ever liked.. and i like it quite a bit! i'd send you a copy if only i knew how to burn one (oh and it's illegal or something, right? ... just have tommy write me an email :-) there's hot lesbian action aka deep explanation of poses at the end, tommy.)

p.s. i think bikram yoga (hot yoga) is the earthly equivalent of hell... it's really freakin' hot and you have some instructor screaming at you to do painful contortions AND you're paying for it.

I may be the only person on the planet who has found a way to make yoga competitive. I totally walk out of the room saying I won...

I second Hatha Yoga notion; it's the basic "real" yoga without any frills, and it's great for flexibility, strength, and peace of mind (seriously). I've heard god awful things about heated yoga, stay away.

As for the pants, I'm anti-yoga pants. Well, I like them as pants to wear aroudn the house, but for yoga, I prefer shorts. When you ballance with one foot up on your leg, I find that pants make said foot slip off. Skin to skin is the way to go.

Catherine, when you are back in DC, you should come to my Body Flow class (Gold's Gym Rockville, Sundays 10:15 AM)! I've always found traditional yoga and Pilates classes to be rather boring -- do a pose, hold it, do another pose, hold it. On the other hand, Body Flow is a combination of yoga, tai chi and Pilates. It's more fluid than a typical yoga class since it's choreographed and really takes advantage of the musical highs and lows. Let me know when you'll be in town and I'll give you a pass. http://www.lesmills.com/site/programs/bodybalance-group-fitness-program.aspx

To answer your questions, no, I don't think you'll become a granola new ager. I'm definitely a Type A and I teach this stuff! I think it's hilarious that I teach other people how to relax and meditate. I've heard from some people that heated yoga is great because you sweat and it feels more like a "real" workout, but I've never tried it myself. I know that Gold's Gym provides yoga mats. You may want to peek in the room one day to see if your gym has them as well or ask at the front desk. As far as clothes, you'll want to wear something form fitting and non-constricting so that you can move easily. I usually wear a sleveless workout top and yoga pants or loose capris. I disagree with Amanda about the pants -- my foot has never slipped off. You don't need to be super-bendy. I always give options in my class so each person can work at his level. Good luck!

Street-fighting is better for tone.

it sounds like you're leaning towards yoga because you want to take a class but don't want to take the standard aerobics class. i highly recommend kickboxing. i have no coordination when it comes to most aerobics classes, but can definitely keep up with all of the kickboxing moves.

nah, i like aerobic classes beyond step (i like kickboxing as well but it's not offered a good time for me). i really am looking something more as a complement for running, which is my preferred cardiovascular activity.

I suggest ashtanga yoga. It's hardcore, disciplined, will give you a kick ass body and doesn't involve heating the room to absurd temperatures (though you will sweat. A lot.). You will definitely develop muscles that you never knew you had. What I particularly like about it is that it's a set series so you have something to strive towards (good for type-A personalities like myself) and you can mark your improvement by how far you can get in the series and how well you can hit the postures. You're always building on what you've already accomplished. I recommend ashtangayogadc.com for when you are back in the district proper.

people like talking about yoga

i recently tried bikram (hot HOT!) yoga in cville. did i mention it was effing hot? the plus is that you are uber bendy by the end and not sore the next day. the minus is that they guy in front of you sweats like a foutain, which is a bit vomitous and adds to the nausea you are already experiencing because it is so damn hot.

anyway, i second ashtanga yoga and pilates. i just suggest finding an instructor who is not a hard core subscriber to the yoga/pilates doctrine and understands that the average person is just there for a workout and doesn't have time to achieve enlightment, thank you very much.