Do you eat the calories you burn exercising?

[mrsp14]

So on myfitnesspal If you add exercise it adds the calories on for you to eat. Ive never added my exercise as I've always thought it counter productive.
I'm starting the insanity workout this week which says you burn approx 1000 cals per session. I don't plan on eating an extra 1000 calories though... But should I be???

 

[Princess Lou]

MFP calculates everything you need to eat. I ate my exercise calories back and dropped a dress size.

The majority of specialists will tell you to eat them back but stop if you feel full.