couple of questions from a newbie..

Hi! I am new and I was wondering if there was a way to add an exercise that is not in the exercises listed. I did the ellipticaln machine at my gym today and I can not find it listed. I chose running and a time that matched my calories burned as an alternative.

My second question, are the machines like the elliptical an treadmill pretty accurate in calorie count if I entered my weight in correctly on them? I weight 320 lbs and did the elliptical for 30 minutes and burned 398 calories according to the machine. Could that be right?

Thanks!