I had some eye strain and think it is because my eye muscles are overused. A doctor told me the muscles in the eye are flat, like tapes, and that I would not feel a muscle ache. I noticed the strain when I focus on different points quickly. I started to pay attention to how I move my eyes and realized I read a lot of text while scrolling, for example reading X posts on mobile while scanning the text at the same time.

Yesterday I was reminded of “Rapid Serial Visual Presentation” for speed reading, where the words are presented so you do not have to move your eyes. I am currently trying it out with a Chrome extension called SwiftRead. I set the text size so it fits into my fovea area. I used a fovea detector website I saw on HN a while ago: https://www.shadertoy.com/view/4dsXzM (make the pattern full screen, then you can see the size of your fovea).

I also learned that I can reduce some of the strain by moving my head more toward the things I am looking at on the screen.