It's not the researcher, it's the reporter!

They just want shocking headlines so you buy their paper (or whatever media they use)--but often, headlines are misconceiving.

The journalist didn't even include a link to the research, the title of the research, or even a quote of the abstract.

I'm accessing the full journal article as from the news story, it appears that they only measured within like groups (i.e. they tested an athlete on an exercise day vs. same athlete on day off; they measured joe-couch-potato on a day that they forced him to exercise vs. his normal couch potato day; but they did not compare between groups: athlete vs. couch potato.)

However, I'm planning to read the entire journal article to make certain that's how they performed the research--have not done that yet (have to go to the library to get it.)