read the whole article. They tried to get some of the women to do high intensity exercise, but they couldn't stick to the protocol.

> Jakicic and his colleagues originally designed their study to measure whether weight loss could really be achieved and maintained through moderate-intensity exercise... or whether it was preferable to engage in shorter bursts of more vigorous-intensity activity... The problem was that not enough of the women stuck with their assigned exercise categories for the researchers to gather enough meaningful data. Within a few months, most of the participants had resorted to exercising as much as they chose to. That left researchers with a slightly different data set than they had planned for

(FWIW I'm all about HIIT, but I don't know how you can get people into it once it becomes inconceivable to do high-intensity work.)