raising calorie intake

I used to eat 1200 calories and run five miles, then play two hours of tennis. I lost a lot of weight and did not realize that was unhealthy. I stopped running as much but continued the same amount of food, I gained to about 120. Tennis season started and i did not weigh myself, but upped my calorie intake to about 1400. I weighed myself a week later and was alarmed to find I weighed 130 lbs. I don't know what to do. I am still very active, and I know I should be eating more. How do I up my calorie intake and lose weight...maybe to about 120 lbs( I am 5' 3)....

Well, upping your calorie intake by 200 calories per day for one week shouldn't make you gain ten pounds...that shouldn't even make you gain one pound, especially if you started playing more tennis when the season started!  The only thing I can think of is that maybe increased exercise made your muscles retain water?  Also, maybe some of the weight gain actually was muscle?  However, eating 1200 calories per day with the amount of exercise you did may have damaged your metabolism, which would make you gain weight easier (but I still don't think you should have gained ten pounds in one week).  If it hasn't been very long since you weighed yourself, I would say give it a few more days, drink lots of water, stay away from salty foods, and see if it starts going down :).

Don't worry about what the scale says for now.  Its not physically possible to gain 10 pounds in a week if you are eating 1400 calories a day, so don't worry about it.  Don't weigh your self for a week and see if the number has gone down a bit.

It is therefore very important to create a balance between exercise, rest and diet to stay healthy and fit. Exercising too much and eating too little will not do you any good so forget about reducing your food and fluid intake to reduce your body size and weight fast. You will get sick if you do that.

assuming ure young (and assuming from ur name that ure 16 years old - born in 92?) then id suggest that its actually because ure not eating enough.

i know people say this alot in this site, and i know it sounds dumb but when you eat way less than u should, ur body tries its best not to lose.

im 17 and 5'3 and probably exersize less than you (atm i cycle 20minutes 5 days a week) and i eat (on average) about 1800 calories a day.

try eating more. you might gain a tiny bit at first, but then ull lose it afterwards.