The usual kind of article, that takes one thing from actual studies and inflates them to prove a point they had before. It starts with the generalization: What kind of cancer? I for example had skin cancer (or maybe I still have it, who knows until it grows). That has nothing to do with fitness or what I eat, but with the solar radiation (yes, the sun). So maybe fitness have effects on some sorts of cancer in some circumstances, but if the article is generalizing in this way I clearly know they have no idea and only write that to promote something they want to promote - in this case doing exercises.