The woman is an avid runner and that alone tends to keep the Body Mass Index quite low. After five kids most women would tend to become candidates for the Walmart People Lycra Spandex fifteen pounds in a ten pound bag photo collection. But those who don't, and work to stay fit, do get thinner. I've seen it with Mrs. Katana. She's proud and I am not complaining.
PS: Sarah is still stunningly gorgeous.