abdominal excercises

my question is this......when i do crunches and work on my oblique muscles (and i sweat like a dog) and enter it into my excercise log as strength training, why doesnt it show me the calories i burn while doing that kind of stuff too? i mean i know im burning calories cuz im sweating and feeling the burn in my abs and stuff but it doesnt add the calories ive burned there to the calories ive burned doing cardio??