Or just make the task smaller and smaller. Can’t finish 5? Do 1! Too much? Just get on the floor and hold the position. This strategy can’t fail, as you can always reduce your goal (and next time have to reduce it less)
I agree and it's important, at the same time, not to trick yourself or push yourself. If you don't feel like doing more, don't. With time, you'll want to do more.
