Hi! You are experiencing a "problem" a lot of us have, and that is genetics! No matter what I do, I can't lose weight quickly-- I'm LUCKY if I can lose a lb./wk, and I have to workout a TON, and not eat that much. Others can eat so much more and workout so much less. It's unfortunate that some of us are like this, but I always look at the bright side, and there can be a lot of other things even worse-- this is something I just have to work through.
Just don't give up, and remember that a lb is still a lb! That's one less lb that you had last week!
Now, there are some things you can try to try to kick your metabolism up a bit (if it is something that you are doing, it will work. If it is genetics, they may work initially, but you'll go back to what your body is comfortable with):
1. Incorporate weightlifting into your workouts (if you don't already)-- building muscle will make you burn more calories
2. Do you eat enough? Yes, with working out a lot, sometimes you need to eat more-- your body needs calories to lose weight. It sounds counterintuitive, but it is true. If you are hungry all the time, or feel sluggish, this could be the problem. Try adding some lean protein or high fiber foods into what you are already eating.
3. Some people will tell you to lower your carb intake, and raise your protein intake. I think this works better for people who don't workout a lot, though-- you need carbs to be active (I'm an anti-low-carb advocate

)
4. My doctor said that if you workout in the morning, it kicks your metabolism into high gear early, and you burn more calories
5. Eat lots of small meals throughout the day instead of a few big meals. It doesn't let your metabolism slow down.
6. Eat breakfast-- your metabolism is slow in the morning.
7. Change up your workout routine-- if you always do the same thing, try something different, workout longer, or increase the intensity
8. Vary your calorie intake from day to day (have a low calorie day, followed by a high calorie day)-- it keeps your body guessing as to how much it needs to metabolize.
Now, if I can only take my own advice
