Here's a little psy background knowledge into this issue: Toughness is correlated to the amount of pain that is shown. There have been numerous studies about the sex difference factor when dealing with pain. The fact is: it's the same. However, our backgrounds dictate us to express the pain in different ways. For example, a study found that potestant women are less likely to shown pain than italian women... in the same logic, perhaps, women (IN GENERAL) have been raised to express pain more than men.
By the way, Jason, you shouldn't trust anecdotal stories as fact. The fact that two women in Asian societies grasping for air during their workouts do not constitute a blanket statement.
And don't trust Dr. Hartman (if he's that same guy from Oprah that made the comment). Remember- Oprah is a women-oriented show with skewed facts for their target audience.
Always question your sources.