@Giga
Do try to keep in mind that if you've already eaten the food, that you must have procured it somehow. Your body doesn't have to prove the means by which it procures food if it has already proven it HAS the food, if you get my meaning. Whether it is through personal ability, or being provided for by another, or some other means, the outcome is already decided.
Plus there is the other factor. That awkward factor which, at least when I received my formal education, still wasn't entirely resolved: The handicap factor. I suspect sexual selection gone out of control plays into it more than the originally proposed notion that personally handicapping oneself proves strength by being able to cope in spite of it. BUT I'm not in the field any more, so I don't suppose it matters.
If you don't know what I'm talking about, take the antlers of many stags for instance. They tend to get FAR larger than they have any need to for the mere purpose of butting heads with other males, to the point where having such ridiculously large things on their skulls is genuinely debilitating. But I figure they get there because the does continually favour the stags with the bigger antlers because bigger is better, and... more importantly... the debilitation doesn't hinder them (the females) personally.
In the case of humans, males typically dominated the hunter role in the past, so there has never been any sort of strong selection for females to be athletically fit. One could even make a reasonable claim that, at least in most of the past, if a female IS that fit that it indicates she wasn't sufficiently provided for and thus may be of inferior ancestry.
Human culture may have changed, but the genetic influence of what our ancestors found desirable in a mate isn't overwritten all that quickly.
In any case, she doesn't look that fat around the middle to me. Not saying you're wrong, but it doesn't even remotely stand out to my eyes. In the grand scheme of what is and isn't believable in this story, I'd still personally count someone of her build being able to hunt effectively as being vaguely believable.