Sometimes the most productive thing you can restore is your ability to care.

When you run empty for long enough, the first thing to go is not your ability to work but your ability to mind about it. Everything gets done at a distance, tasks and people alike, and you notice a flatness where interest used to be. Nothing you produce in that condition will be as good as what you make when the caring is intact, and no amount of effort substitutes for it.

If things have started to feel grey, treat that as the priority rather than an inconvenience. Rest, time outside, contact with people you like. Restoring the caring restores everything downstream of it.