The author is being really cautious:
""Our findings suggest that beyond focusing on losing weight to improve metabolic health, there may be a role for maintaining fitness and building muscle mass," says Preethi Srikanthan, an assistant professor of medicine in the division of endocrinology at UCLA's David Geffen School of Medicine."
Apparently, they found "for each 10% increase in the skeletal muscle index — the ratio of muscle mass to total body weight — there was a corresponding 11% reduction in insulin resistance and a 12% decrease in pre-diabetes."
It would be _really nice_ if we could stop thinking about exercise and fitness as a way to lose weight, but as a way to become healthier. Then, if weight loss happens, hey, yay. But if weight loss does not happen, but all kinds of other numbers improve (bp down, LDL down, CRP down, etc.), we can still feel like the exercise was Worth It.