TL;DR - running whilst looking at stuff promotes activity in the visual cortex (the bit of the brain which organises sight).
Basically, if animals have limited sight in one eye from birth (in the case of these mice they had their one eye covered up) then the corresponding part of the brain has less neural activity.
eye that was covered up has more visual stimulation at this point, the corresponding part of the brain also fires more frequently (and more robustly) which increases the amount of activity in that area. This in turn would lead to
increased sensitivity and increased visual acuity in these mice.
What does any of this mean?
It means that the adult brain (in mice) is much more capable of "reprogramming" itself than we originally believed.
Apparently old mice can learn new tricks!
If studies in humans show similar results, that would mean that restoration (or certainly
partial restoration) of sight would be possible. What an amazing breakthrough that would be!
So was the study actually any good?
Well, my main point would be that it has only been done on mice. Scientists aren't allowed to take babies and cover one of their eyes up until they're adult and then test it out on them to see if it works. We could take humans that already have a condition that leads to partial or no sight in one eye and see whether it works, but the first round of testing is much easier to do on mice (for various reasons that I've already explained - the main one being it's cheaper to arrange), so now that we can see there is some sort of response we can move on to human subjects.
It does make sense that the brain retains this level of plasticity into adulthood - environments change and even
adult organisms need to adapt to change.
So does running improve sight all around?
Personally I find my sight goes more blurry....could be on account of my poor cardio fitness though.... :p in theory though (and according to this theory) all of our senses should respond to the increase in pace - we're moving faster
through our environmend and we're being bombarded with information at a faster pace.
It's well known that running has many benefits - could increased eyesight be one of them? I certainly hope so.