huntnma,

In my opinion, that's too much food for a Cocker Spaniel. Especially for an inactive one. My lab gets that same amount of food (about a cup in the morning and a cup in the evening). He's in excellent shape according to our vet (he could actually lose a few pounds), he's got tons of energy, and he's ready to eat when I put food in his bowl.

The correct amount of dog food also depends on the dog food's level of quality. I used to feed Pedigree, and fed about 4 cups a day of that, compared to 2 cups a day of Iams. A dog requires more of a lesser quality feed than a higher quality feed due to the indigestable ingredients found in the cheaper brand.

Your friend's dog is probably getting too much to eat, given its lack of exercise.