First, when you say "I am currently on a diet that allows me to consume approximately 1,200 calories in a day", how is this calculated? Is this your daily caloric needs? Or have you subtracted an amount from your daily caloric needs?
If your goal is to lose fat then in order to lose fat safely and effectively you need to create a calorie deficit of 250-500 calories a day. This should accumulate to about a .5 to 1 lb fat loss per week. (3500 calories equals 1 lb.) This should be your ideal goal to lose .5 to 1 lb of body fat per week. If you lose any more then this you are most likely losing muscle and/or water weight along with losing body fat. YOU DO NOT WANT TO LOSE MUSCLE!! If you lose muscle your metabolism will slow down causing you to eventually gain weight.
Start here: http://www.freedieting.com/tools/calorie_calculato...
Find out your daily caloric needs. Then add your 600 calories that you burn during your workout session to your daily caloric needs. Finally, subtract 250-500 calories from this total.
Your daily caloric needs are 1,500 Calories
+ 600 Calories Burned during Workout
= 2,100 Calories (This is your maintenance amount. Eat this amount to maintain your current weight)
- 500 Calories
= 1,600 Calories (This is your calorie deficit amount. Eat this amount to lose weight)
If your goal was to gain weight (put on muscle) you would add 250-500 calories to your maintenance amount.)
Best of luck to you in achieving all of your goals!