Some weeks ago I stumbled upon two facts.
Fact 1: The optimum amount of sleep is 7 hours. People who slept 7 hours felt most refreshed according to a study.
Reality1: Sometimes works and I can carry on for the whole day, feeling energetic all the way through. But sometimes I have a headache and sleep, like, 9 hours.
Fact 2: People get used to new sleeping regimes in 21 days, i.e. 3 weeks.
Reality 2: Have tried to carry on for some weeks now. There are some slips but overall looks like this fact is true. My body is adapting the 7-hour routine! Yay! This means I sleep 1-2 hours less every day. It’s 7-14 extra hours spent awake per week. Wow! What should I do with all this time? I know, edit, edit, edit. Write, write, write.