how long can you concentrate in your studies?

When I was still studying in UP, I can take 3-5 hours non-stop in studying. In between I take a short nap when I'm really sleepy. I eat nuts and chocolates, and drink isotonic water or Gatorade when studying. I used to listen to music with an iPod while studying.

i can study continuously for about 30-50 minutes. Yes, i really have a problem with my attention span. I get distracted easily. Sometimes, whenever theres a need to really study the subject matter, I'll lock myself in my room and study there. Sometimes I put ear plugs just to keep the noise away.. .. Well, whenever there is a need to refresh myself, sometimes i would go to the refrigerator and look for something to eat. Sometimes, i just surf the net for updates in manga and anime series (this takes a lot of discipline ). And sometimes, i just roam around the house.. hahaha.. because its tiring to sit down all day..

for me, it really difficult for me to continuously study... i think the most longer thime i can concentrate mayb is 10-15 minutes? hahaha... i'm to read but not the text book... if 1 me 2 read the text, sure i will fall sleep n go n search for other things to do.... like watching tv, reading my lovely novel, comic.... so, every time my exam, i will b very stress coz not study... but i still doing the same thing till now... hahaha... so i will try 2 concentrate in the class, so i not need to study or doing revision... hahaha....

to be honest, i can not hold on more times when i study ,especially studing some objects that i did not interesed in .to refresh myself beteen this studies, i often playing games, such as basketball, football or computer games. i thought we can relax ourselves by this ways.i hope my advices can help you . thank you .