Two articles caught my eye today.
The first was TIME Magazine, saying that "Fitness experts are now advising against doing too many sit-ups for risk of back injury."
Yes, that's true, if you mean by "now" you mean "for at least the past 10 years." This was old news 5 years ago. It's true, but badly out of date.
Why Fitness Experts Have Turned Against Sit-Ups
And for all of the "fit and obese is okay" sorts of news I've seen pop up, here is a study of 1.3 million Swedish men that seems to indicate that fit + lean beats fit + obese.
Fitness more protective among normal-weight people
Both are true. Both are useful. TIME is just well behind the curve here. And the study in the second implies that you do still need to control your body fat. Not a terrible surprise, but good to know and good to have for reference.