I think it's probably best to work out in the morning to get it out of the way. My ultimate top tip is to drag yourself, even if you have to roll yourself out of your bed and in to a sit-up - it's really not that bad once you start.
“There may be fairies at the bottom of the garden. There is no evidence for it, but you can't prove that there aren't any, so shouldn't we be agnostic with respect to fairies?”
“In our racist, sexist society, Christmas is the 8 hours when we stop killing each other and gratutious over eating is encouraged so that the starving and other people in the world can die!”