http://www.amazon.co.uk/Ultrafit-331100000022-F-Bike/dp/B003FSTA0U/ref=sr_1_1?s=sports&ie=UTF8&qid=1316673481&sr=1-1

what will it improve for me because i want to run faster and gain a lot of stamina.
is this exercise bike good enough and im on a tight budget also i am 15 years old.