Translation:The exercise is tiring but good for your health.
“...good for one’s health” ought to be accepted. That’s three DL “fails” through no fault of my own this morning and I’m not even half way through the first exercise.
I agree that the first the should be left out but the second should be your health
I think it depends on the context. As a general statement, you’re right. If you are discussing a particular exercise with your personal trainer, he would include “The”. So DL ought to accept both.