Fair and Blind

Instapundit:

TOO MUCH TIME INDOORS causes myopia?

I've wondered about that since I have myopia. There weren't any sports or activities at my school in Saudi Arabia. With the weekly exception of a cricket game with friends, I spent practically all my time indoors reading novels and magazines. It was the same in Pakistan; though, the cricket frequency was a bit higher.

Comments

[David Boxenhorn]

Our eyes are not evolved for looking close-up for long periods of time. If you are indoors for a long time, look out the window, into the distance. You should notice, immediately, a feeling of relaxation. It's good for you, do it often.

[Classical Liberal]

That's my understanding as well, more or less (I'm nearsighted as well). As I understand it nearsightedness is in part genetic, but also caused by eye strain. When your eyes are focused up close, in particular when reading or using a computer, the muscles that shape the lens are contracted. When you focus on a distant object they relax, letting the lens return to its normal shape.

This is just like too much continuous contraction of the skeletal muscles (hard exercise) can cause a cramp or strain.

I've also heard (though I don't know for sure it this is so) that it can be helpful to let your eyes follow a line to distant focusing. It there is a powerline, wall, curb, or any sort of line that you can look at in the near distance, and then let your eye follow it out to a greater distance, this is sort of like a warm down for the focusing mucles of the eye.

[Thanks. I'll keep this in mind. -- Isaac S.]