Best Way To Build Stamina?

[Eclipse]

I'm a brilliant runner and use to be fab at cross country. But after spending most of my days inside on Habbo I have not been getting the lung exercise needed. So I am like a rocket with the 100m but as the distance gets further, I start to struggle. Never the less, I still am very good compared to most people my age but just not as good as I know I can be. So any advice on how to build stamina would be hugely appreciated.

You should do the beep test.
Download the beep test off the internet, just search google.
Make sure you have a clear spaces and measure 20m.
See how far you get, then keep pushing yourself.

[Soy]

You should do the beep test.
Download the beep test off the internet, just search google.
Make sure you have a clear spaces and measure 20m.
See how far you get, then keep pushing yourself.

Yeah bleep test is a great cardiovascular excersise. Remember to run on a soft surface like grass or sand, taking as much strain off your joints as possible

[GoldSolid]

I did the beep test at school in year 9, it killed me lol. I've got rubbish stamina but I'm really fast at short distances..