It has been said in the Buddhist teachings that without exertion, you
cannot journey on the path at all. When you are taking a holiday or a
vacation, you are very inspired to wake up in the morning, because you
are expecting to have a tremendous experience. Exertion is like the
minute before you wake up on a holiday trip: you trust that you are
going to have a good time, but you also have to put your effort into it.
So true exertion is some kind of celebration and joy, which is free
from laziness.
Source: Training the Mind and Cultivating Loving Kindness, pages 70 to 71