I don't have access to the article, but the ending of the abstract caught my eye:

>These findings suggest caution in claims and recommendations linking regular physical exercise to cognitive benefits in the healthy human population until more reliable causal evidence accumulates.

What do they mean by "the healthy human population"?

Does it mean that if you're already healthy, the can't prove that there's any added cognition benefits from exercise? So no depression, overweight, etc. included in the studies? Does "healthy" account for sleep patterns? General activity levels?

I've got so many questions, and the publisher's greed won't let me try to find the answers..