As someone with concerning myopia, the 20-20-20 rule has always been a difficult habit to make.
20 minutes is not long and getting up to look at something outside is quite demanding. I often have 2-4 hour sessions without looking away if I'm in flow or distracted.
20 minutes is not long and getting up to look at something outside is quite demanding. I often have 2-4 hour sessions without looking away if I'm in flow or distracted.