My caption idea:
"That's it? 10 lousy sit-ups, and you're already tired? Sure, it's 5 more than yesterday, but that's still pathetic! What do I have to do to motivate you? Take off my top and let you smooch and motorboat my tits whenever you come back up? ... Huh. I never thought of that before, that sounds like a great idea! You better be prepared for mommy's titties, sweetie!"