here is a real way to test you fitness. it's called the shuttle run.
Step 1: Just Download the File: Http://www.soccerclinics.com/ICAFitnessMembers/6766/with_flash/html/Testing/TestingBeepTest.html
now mesure twenty meters and and draw two lines. when it beeps run get both feet past twenty metrs. then wait. once it beeps again repeat. you must run after the beep. see what level you can achive. the world record is ninteen