I have always been told reading in low light will strain your eyes. I am just confused how this works, eyes aren’t muscles I don’t think.
In: 5
Light= radiation, therefore too much light *burns* the eyes
Pupils move to dilate. Movement = muscle (or something similar)
Too much light= strain to keep pupil small
Too little light= strain to keep pupil all the way open **and** focus the eye on something it can barely see at the same time
Eyes aren’t muscles themselves but they have muscles. There are [several muscles that control your eye’s movement](https://teachmeanatomy.info/wp-content/uploads/The-Extraocular-Muscles-of-the-Eye.jpg.webp) and then also [muscles that control the size of the pupil and the shape of the lens](https://www.researchgate.net/publication/327821522/figure/fig1/AS:941454138568754@1601471566940/The-structure-and-development-of-the-human-iris-a-Cartoon-of-the-iris-musculature.png). Those muscles are always working anytime you focus on something. Normally, your vision moves around when you look at different things and focus on objects and different distances, so those muscles all get a chance to relax at time, but focusing on something like a book, phone screen, or computer screen for a long period of time keeps those muscles working and they get tired, just like your leg muscles might get tired after being on your feet all day.
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