hey um i've been riding now for bout 5 years and a good friend of mine whats to start biking but heres the problem: he is overweight but he is fit(if that makes sense)he can run faster than most people he can run a mile in 10 mins. but i dunno if he can beome a biker im teaching him but he just cant do the stuff right .dont get me wrong i encourage this guy everyday i try to teach him. but what do you guys think .thanks