How do I prevent further progression of myopia when studying?

Perceptron

When studying for long periods, does looking up at a distance make a difference?
Would looking up periodic after 30 minutes from the book any helpful?

Perceptron	How do I prevent further progression of myopia when studying? When studying for long periods, does looking up at a distance make a difference? Would looking up periodic after 30 minutes from the book any helpful?