So I sit on my butt all day long at work. I have a desk job. The only activity I get is when I go to the gym-which is a new thing for me. I weight 270lbs and have been limiting my calories to 1200 a day and my weight has not budged. So I have started excersizing and now I'm gaining weight. I'm pretty much convinced that I need to do something drastic-like limiting my calories to 500 a day because I'm not getting results and I'm sick of it.

How long has it been since you started exercising? Whenever I start something new or up the intensity, I gain a bit of water weight. It goes away after my body recovers/adjusts.

How long have you been eating 1200cal /day? When did you start the gym? What are you doing?

Water weight is usually the culprit. Give it a few days. The water repairs the itty bitty tears in your muscles

I'd actually recommend doing the opposite and increase your calories. It may not make 'sense' but trust me it works. Eating 1200 calories a day when you're exercising is not enough. Bump them up to at least 1600 and stay there for at least two weeks. You should see the pounds start to melt away.

Well, weight isn't always fat. If you're exercising, weight gain also comes from building muscle. When I started slipping in my fitness routine - I'd keep checking my weight hoping it'd stay the same despite no exercise and it did for about a week or so, then one morning I woke up and noticeably felt bigger- in my upper arms and tummy - but my weight was still the same. I think it's cuz whatever muscle I had had now turned into pure flab And it repeated as I gradually continued to gain weight and got to where I am...totally unfit, unhealthy and flabby. SO - don't focus so much on your weight. Keep an eye on how your clothes fit too, or measure yourself weekly. Even if you may be gaining weight or maintaining despite exercise, it could be the muscle talking.
If you've gained ALOT though...despite exercise and limited calories... maybe you should consult with a professional of some kind? It may be something else that you should have checked Don't be discouraged!! It's wonderful what you're doing and you should feel good about that! I don't gym nor do I count my calories... :-/ I'm starting with 20 minute videos... I also sit on my butt all day long.

When you increase your activity level, you damage the muscles being used, but in most cases it's "good damage." The small muscle tears trigger a process that strengthens existing muscle and creates and lays down new muscle where the micro-injuries occurred.

Even though these micro-injuries are a GOOD thing in the long run, the body still reacts to them by going into healing mode.

Healing mode requires lots of water, so your body will hold on to more water (from the food and beverages you take in). This results in a temporary water weight gain. When the extra water isn't needed for healing any more, your body will get rid of it and you'll see the fat losses that the water prevented you from seeing.

Illness or injury of any kind can result in water weight gain. Last summer, I gained 10 lbs overnight as a result of a fairly bad sunburn. Even a cold or flu can cause temporary "healing mode" water retention.

What she said! Just keep up the exercise and water weight will come off eventually. That's the only sucky part about exercise, heh.

I also think what matters is what you are eating. Last year I exercised like crazy, and gained about 10 lbs. This year, I'm probably doing less on the exercise, but I've been losing about 6lbs/months so far. So, I'm down about 37# for the year to date.

A lot of what I cut out is processed grains (pasta/most bread/most rice). When I do have grains, they're whole when possible. I also stopped eating a lot of more sugary fruits. No juice; only whole fruits. Focus on vegetables and lean proteins, and also fiber. Walnuts are at my desk to snack on.

I don't know if it'll work for the OP, but it's helped me. I also agree that the calories may need to go up a little. Sometimes I have a "pig out" day when I'm really hungry and dragging. (Not junk food...just more food.) The end result is usually a weight loss, vs. if I just eat more food that I know isn't as good for me, then I get a gain I've got to work off.

Forgot to add...look to what's happening w/your size, as others have mentioned. Last year, when I kept gaining, people kept telling me I looked great and was losing weight...but I wasn't. It was frustrating to know I was actually gaining, even if I'd lost fat/gained muscle. But at least some of the flab was going and the better muscle was sticking around.

What they said! I gained like 10 lbs at one point in a week when I started doing a work out DVD. I was super sore. I kept up with the DVD and once that soreness went away - the weight went with it.

It takes time!