Protecting your weekend isn’t lazy. A tired version of you helps nobody on Monday.
STILLNESS
STILLNESS
Calling it lazy assumes rest produces nothing, which only holds if you ignore everything that happens afterwards. A tired version of you is worse at every job it gets handed: slower on Monday, shorter with people, worse at the exam, less good to be around. A weekend is not a reward for the week. It is part of how the week works at all.
Block out one stretch this weekend and treat it as booked when somebody asks. You need no better reason than that it is taken. Then look at your Monday and see whether it paid for itself.
What do you give away on Saturdays that Monday needs back?
Free, with nothing to buy inside it.