[Blarg]

The thing about doing a sport is always the best advice because getting in shape and staying in shape isn't good lasting motivation for most people. They'll get tired of the idea eventually and stop working out, or they'll figure they've improved so they're in good enough shape, and slack off so they have the same problem they started with. It's a rare person who can stick to a long-term fitness routine just to get in shape or keep the pounds off. People are generally just not built with that kind of discipline and are not about to acquire it anytime soon.

If you can't get into a sport, you should seek outside motivation for a reason to move your bod around that goes beyond doing it just because you have to.

You have to develop an actual interest in being good at something with your body. This type of thing can motivate you for years at a time, no problem, or even a whole lifetime. For some that's sport. For others it can be personal goals, like finally being able to do the splits or kick head-high, or becoming not reasonably slim, or whatever, but actually strong or fast or coordinated. (DDR is good for that reason -- you have something to aspire to and the fitness part is only incidental.) If you're going to the gym to become strong or good at a sport, it's much more motivating than just going to the gym to not look bad. You have something to shoot for where the rewards are psychologically really positive, and the goal changes.

With just getting or staying "fit-looking," the goal never changes and there's never really anything to achieve that can push you for years and years on end and get that last extra ounce of effort out of you(and off your gut). You will eventually find the goal of "just five more pounds" dull and unrewarding, especially since all it's working towards is being quite unexceptional -- that is, looking more the way you should. Rather than being able to do something really cool or fun or outstanding, that is better than just "okay." As in, Whew, I finally look okay! Yuck. Trying to get "not bad" is no motivation at all compared to trying to get good. People need a little more of a possibility for triumphs outside of just showing up to do exercise, and not failing. Not screwing up is a sad, dull motivator.

Even women can get strong. It's very foreign to the concepts of womanhood society sticks on them, but it works the same for them as it does for men. And even dedicated women find it very hard to put on the kind of mass that makes them look masculine. Short of steroids, you can work out like crazy and you're not going to get significant muscle bulk as a woman.

I'd suggest getting yourself some fitness goals rather than settling for essentially a grind you feel obligated to do. Be that yoga chick, or that strong chick, or that coordinated fluidly moving chick, or all of that. You can do it all at home and without spending a ton of money. Spending $1500 on an exercise machine that does only one thing probably won't motivate you any more than it usually motivates anyone else. You're very unlikely to be all that special or different that way. What you need is not the very best exercise hardware, but a lasting goal that makes being in shape the beginning of a long and satisfying process.