Obviously being healthy doesn't mean there wont be occasional setbacks. Catching a cold or flu is never fun but In an optimistic viewpoint, this is our bodies way of telling us to take a break because there is a weak point in our body.

This is where the concept of balance enters. Perhaps you are keeping to a fitness routine that involves vigorous workouts. Times of rest needs to be incorporated so as not to over stress the body. Without this balance injury is assured.