When I use the computer or smart phone all day I always feel weird when I play soccer at night like I can focus why does this happen?

Likely the screen,,, This is likely due to the screen and its glare. it might be best to take a 10 minute break for you eyes to re-adjust before doing another activity. Best of luck.

Related Questions

When I use the computer or smart phone all day I always feel weird when I play soccer at night like I can't focus why does this happen?

Adjustment . It probably gets better as you play, yes ? that's your nervous system habituating to a stimulus, and then acclimating slowly to a total change in environment. You might want to do something outside after the computer time, and before the soccer, to clear your head. Read more...
Can try changing. If things are not the way they seem they should be, one can try altering his daily activities, daily bedtime & waking time, dietary habits, etc... Medications, alcohol intake, caffeine use, etc., can also make a noticeable difference. Go back to nature and try to see how humans evolved to be like over the past many thousands of years, to figure out what activity today might be causing a problem. Read more...