While I understand the principle to which you are alluding, it probably does not apply to exercise. The body has an amazing ability to recuperate from occasional assaults of most kinds. Hence, you would have to exercise chronically, eat processed foods chronically, have chronic stress (which often happens in our society), etc., etc. to have an impact on health.
Yet if you got to the point where you exercised chronically you would, among other things, be fueling your body with the very hormones that mitigate the harmful impact of negative feelings, particularly negative feelings towards exercise as a chore. Different strokes for different folks, I did not mean to imply that everyone should dance or trail run, and there may be physical limitations that prevent someone from exercising regularly. It's kind of a Catch-22. If you could exercise so much that it would impact your health from the negative feelings of a chore, there would be too many beneficial hormones for that to happen.
On edit: I should add that you can, in fact, get too much exercise, or exercise unwisely. There are two hormones produced by exercise, adrenaline and cortisol, that are bad if produced in excess. Cortisol is particularly bad and happens to be the hormone produced by chronic stress as well.
