It’s becoming well known that Asian children suffer a high incidence of myopia, with perhaps 75% of children requiring corrective lenses by their mid teens. The reasons might be genetic, but that wouldn’t adequately explain any recent increase in myopia rates. It is postulated that the reason these kids might suffer so much myopia is that they are studious from a very young age and spend a lot of time on close focus work – reading books and in front of computer screens. http://www.myopia.org/myopiaprevalence.htm
In contrast, children in Australia suffer a much lower incidence of myopia at comparative ages. Again, the reason postulated is that Australian children still spend much of their childhood outdoors, with far field focus accounting for much of their sight time. It’s a big country. When you look around, all that you can see is often the horizon. This is especially true when living on the coast (where most Australians live). There is a wide, Pacific Ocean and all you can see, far our to sea, is where the sky meets the water. http://hpr1.com/tech/article/myopia_causes_still_out_of_focus/
The native Aboriginal people of Australia were renown for their amazingly clear, sharp eyesight, far better in quality than that of the colonial settlers. Once again, gazing for long periods of time on far distant horizons was a commonplace, but there is also a lot of sunlight. That might have something to do with it too.
So it might be that keeping yourself focused on the horizon and remaining in sunlight might prevent you from suffering short sightedness. There’s a poetic metaphor and a lesson for us all in that, I think.
In all that you do, stay focused on your distant horizon and try to be where it’s bright and sunny.