actually i have, 200M in 24,5 seconds back in gr 8, long looong time ago, i know your supposed to take long strides ect, but you can still take long strides while kicking your legs hard, and to kick your legs hard and fast you have to be tense to a certain extent. If you watch all the other runners they are pretty fuckin tense, usain is just an exception cause he has like 5 foot long legs.